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==Mathematics==
==Mathematics==
* Seven is the fourth [[prime number]] and a [[Mersenne prime]] (since {{nowrap|1=2{{sup|3}} − 1 = 7}}).
* Seven, the fourth [[prime number]], is not only a [[Mersenne prime]] (since {{nowrap|1=2{{sup|3}} − 1 = 7}}) but also a [[double Mersenne prime]] since the exponent, 3, is itself a Mersenne prime. It is also a [[Newman–Shanks–Williams prime]],<ref>{{Cite web|url=https://oeis.org/A088165|title=Sloane's A088165 : NSW primes|last=|first=|date=|website=The On-Line Encyclopedia of Integer Sequences|publisher=OEIS Foundation|access-date=2016-06-01}}</ref> a [[Woodall prime]],<ref>{{Cite web|url=https://oeis.org/A050918|title=Sloane's A050918 : Woodall primes|last=|first=|date=|website=The On-Line Encyclopedia of Integer Sequences|publisher=OEIS Foundation|access-date=2016-06-01}}</ref> a [[factorial prime]],<ref>{{Cite web|url=https://oeis.org/A088054|title=Sloane's A088054 : Factorial primes|last=|first=|date=|website=The On-Line Encyclopedia of Integer Sequences|publisher=OEIS Foundation|access-date=2016-06-01}}</ref> a [[lucky prime]],<ref>{{Cite web|url=https://oeis.org/A031157|title=Sloane's A031157 : Numbers that are both lucky and prime|last=|first=|date=|website=The On-Line Encyclopedia of Integer Sequences|publisher=OEIS Foundation|access-date=2016-06-01}}</ref> a [[happy number]] (happy prime),<ref>{{Cite web|url=https://oeis.org/A035497|title=Sloane's A035497 : Happy primes|last=|first=|date=|website=The On-Line Encyclopedia of Integer Sequences|publisher=OEIS Foundation|access-date=2016-06-01}}</ref> a [[safe prime]] (the only Mersenne safe prime), and the fourth [[Heegner number]].<ref>{{Cite web|url=https://oeis.org/A003173|title=Sloane's A003173 : Heegner numbers|last=|first=|date=|website=The On-Line Encyclopedia of Integer Sequences|publisher=OEIS Foundation|access-date=2016-06-01}}</ref>
* Seven is the lowest natural number that cannot be represented as the sum of the squares of three integers. (See [[Lagrange's four-square theorem#Historical development]].)
* Seven is the lowest natural number that cannot be represented as the sum of the squares of three integers. (See [[Lagrange's four-square theorem#Historical development]].)
* Seven is the [[aliquot sum]] of one number, the [[cubic number]] {{num|8}} and is the base of the 7-aliquot tree.
* ''n'' = 7 is the first natural number for which the next statement does not hold: "Two [[nilpotent]] [[endomorphism]]s from '''C'''<sup>''n''</sup> with the same [[minimal polynomial (linear algebra)|minimal polynomial]] and the same rank are similar."
* 7 is the only number ''D'' for which the equation {{nowrap|1=2{{sup|''n''}} − ''D'' = ''x''{{sup|2}}}} has more than two solutions for ''n'' and ''x'' natural. In particular, the equation {{nowrap|1=2{{sup|''n''}} − 7 = ''x''{{sup|2}}}} is known as the [[Ramanujan–Nagell equation]].
* 7 is the only dimension, besides the familiar 3, in which a vector [[cross product]] can [[seven-dimensional cross product|be defined]].
* 7 is the only dimension, besides the familiar 3, in which a vector [[cross product]] can [[seven-dimensional cross product|be defined]].
* A seven-sided shape is a [[heptagon]]. The regular ''n''-gons for ''n'' ≤ 6 can be constructed by [[compass and straightedge]] alone, but the regular heptagon cannot.
* 7 is the lowest [[dimension]] of a known [[exotic sphere]], although there may exist as yet unknown exotic smooth structures on the 4-dimensional sphere.
* [[999999 (number)|999,999]] divided by 7 is exactly [[142857 (number)|142,857]]. Therefore, when a [[vulgar fraction]] with 7 in the [[denominator]] is converted to a [[decimal]] expansion, the result has the same six-[[numerical digit|digit]] repeating sequence after the decimal point, but the sequence can start with any of those six digits.<ref>Bryan Bunch, ''[[The Kingdom of Infinite Number]]''. New York: W. H. Freeman & Company (2000): 82</ref> For example, 1/7&nbsp;=&nbsp;0.142857&nbsp;142857... and 2/7&nbsp;=&nbsp;0.285714&nbsp;285714....
:In fact, if one sorts the digits in the number 142857 in ascending order, 124578, it is possible to know from which of the digits the decimal part of the number is going to begin with. The remainder of dividing any number by 7 will give the position in the sequence 124578 that the decimal part of the resulting number will start. For example, 628 ÷ 7 = {{sfrac|89|5|7}}; here 5 is the remainder, and would correspond to number 7 in the ranking of the ascending sequence. So in this case, 628 ÷ 7 = 89.714285. Another example, 5238 ÷ 7 = {{sfrac|748|2|7}}, hence the remainder is 2, and this corresponds to number 2 in the sequence. In this case, 5238 ÷ 7 = 748.285714.
* A seven-sided shape is a [[heptagon]]. The regular ''n''-gons for ''n'' ≤ 6 can be constructed by [[compass and straightedge]] alone, but the regular heptagon cannot. [[Figurate number]]s representing heptagons (including seven) are called [[heptagonal number]]s. Seven is also a [[centered hexagonal number]].<ref>{{Cite web|url=https://oeis.org/A003215|title=Sloane's A003215 : Hex (or centered hexagonal) numbers|last=|first=|date=|website=The On-Line Encyclopedia of Integer Sequences|publisher=OEIS Foundation|access-date=2016-06-01}}</ref>
* Seven is the first integer reciprocal ([[multiplicative inverse]]) with infinitely repeating [[sexagesimal]] representation.
* There are seven [[frieze group]]s, the [[group (mathematics)|groups]] consisting of [[symmetry group|symmetries]] of the plane whose group of [[translation (mathematics)|translations]] is [[isomorphic]] to the group of [[integer]]s.
* There are seven [[frieze group]]s, the [[group (mathematics)|groups]] consisting of [[symmetry group|symmetries]] of the plane whose group of [[translation (mathematics)|translations]] is [[isomorphic]] to the group of [[integer]]s.
* There are seven fundamental types of [[catastrophe theory|catastrophes]].
* There are seven fundamental types of [[catastrophe theory|catastrophes]].
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* When rolling two standard six-sided [[dice]], seven has a 6 in {{num|36}} (or {{sfrac|6}}) probability of being rolled (1–6, 6–1, 2–5, 5–2, 3–4, or 4–3), the greatest of any number.
* When rolling two standard six-sided [[dice]], seven has a 6 in {{num|36}} (or {{sfrac|6}}) probability of being rolled (1–6, 6–1, 2–5, 5–2, 3–4, or 4–3), the greatest of any number.
* The [[Millennium Prize Problems]] are seven problems in [[mathematics]] that were stated by the [[Clay Mathematics Institute]] in 2000. Currently, six of the problems remain [[unsolved problems in mathematics|unsolved]].
* The [[Millennium Prize Problems]] are seven problems in [[mathematics]] that were stated by the [[Clay Mathematics Institute]] in 2000. Currently, six of the problems remain [[unsolved problems in mathematics|unsolved]].
* [[999999 (number)|999,999]] divided by 7 is exactly [[142857 (number)|142,857]].


===Numeral systems===
===Numeral systems===

Revision as of 00:25, 9 May 2017

← 6 7 8 →
−1 0 1 2 3 4 5 6 7 8 9
Cardinalseven
Ordinal7th
(seventh)
Numeral systemseptenary
Factorizationprime
Prime4th
Divisors1, 7
Greek numeralΖ´
Roman numeralVII
Roman numeral (unicode)Ⅶ, ⅶ
Greek prefixhepta-/hept-
Latin prefixseptua-
Binary1112
Ternary213
Senary116
Octal78
Duodecimal712
Hexadecimal716
Greek numeralZ, ζ
Amharic
Arabic٧
Persian & Kurdish٧
Urdu۷
Bengali
Chinese numeral七(qi)
Devanāgarī (sat)
Telugu
Tamil
Hebrewז (Zayin)
Khmer
Thai
Saraiki٧
Kannada

7 (seven; /ˈsɛvən/) is the natural number following 6 and preceding 8.

Mathematics

Graph of the probability distribution of the sum of 2 six-sided dice
  • When rolling two standard six-sided dice, seven has a 6 in 36 (or 1/6) probability of being rolled (1–6, 6–1, 2–5, 5–2, 3–4, or 4–3), the greatest of any number.
  • The Millennium Prize Problems are seven problems in mathematics that were stated by the Clay Mathematics Institute in 2000. Currently, six of the problems remain unsolved.
  • 999,999 divided by 7 is exactly 142,857.

Numeral systems

Base Numeral system
2 binary 111
3 ternary 21
4 quaternary 13
5 quinary 12
6 senary 11
7 septenary 10
over 7 (octal, decimal, etc.) 7

In quaternary, 7 is the smallest prime with a composite sum of digits.

Basic calculations

Multiplication 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 50 100 1000
7 × x 7 14 21 28 35 42 49 56 63 70 77 84 91 98 105 112 119 126 133 140 147 154 161 168 175 350 700 7000
Division 1 2 3 4 5 6 7 8 9 10
11 12 13 14 15
7 ÷ x 7 3.5 2.3 1.75 1.4 1.16 1 0.875 0.7 0.7
0.63 0.583 0.538461 0.5 0.46
x ÷ 7 0.142857 0.285714 0.428571 0.571428 0.714285 0.857142 1 1.142857 1.285714 1.428571
1.571428 1.714285 1.857142 2 2.142857
Exponentiation 1 2 3 4 5 6 7 8 9 10 11 12 13
7x 7 49 343 2401 16807 117649 823543 5764801 40353607 282475249 1977326743 13841287201 96889010407
x7 1 128 2187 16384 78125 279936 823543 2097152 4782969 10000000 19487171 35831808 62748517
Radix 1 5 10 15 20 25 30 40 50 60 70 80 90 100
110 120 130 140 150 200 250 500 1000 10000 100000 1000000
x7 1 5 137 217 267 347 427 557 1017 1147 1307 1437 1567 2027
2157 2317 2447 2607 3037 4047 5057 13137 26267 411047 5643557 113333117

Evolution of the glyph

In the beginning, various Hindus wrote 7 more or less in one stroke as a curve that looks like an uppercase J vertically inverted. The western Ghubar Arabs' main contribution was to make the longer line diagonal rather than straight, though they showed some tendencies to making the character more rectilinear. The eastern Arabs developed the character from a 6-look-alike into an uppercase V-look-alike. Both modern Arab forms influenced the European form, a two-stroke character consisting of a horizontal upper line joined at its right to a line going down to the bottom left corner, a line that is slightly curved in some font variants. As is the case with the European glyph, the Cham and Khmer glyph for 7 also evolved to look like their glyph for 1, though in a different way, so they were also concerned with making their 7 more different. For the Khmer this often involved adding a horizontal line above the glyph.[1] This is analogous to the horizontal stroke through the middle that is sometimes used in handwriting in the Western world but which is almost never used in computer fonts. This horizontal stroke is, however, important to distinguish the glyph for seven from the glyph for one in writings that use a long upstroke in the glyph for 1. In some Greek dialects of early 12th century the longer line diagonal was drawn in a rather semicircular transverse line.

On the seven-segment displays of pocket calculators and digital watches, 7 is the number with the most common glyph variation (1, 6 and 9 also have variant glyphs). Most calculators use three line segments, but on Sharp, Casio, and a few other brands of calculators, 7 is written with four line segments because, in Japan, Korea and Taiwan 7 is written as ① in the illustration to the right.

While the shape of the 7 character has an ascender in most modern typefaces, in typefaces with text figures the character usually has a descender, as, for example, in .

Most people in Continental Europe[2] and increasingly in the UK and Ireland as well as Latin America write 7 with a line in the middle ("7"), sometimes with the top line crooked. The line through the middle is useful to clearly differentiate the character from the number one, as these can appear similar when written in certain styles of handwriting. This glyph is used in official handwriting rules for primary school in Russia, Ukraine, Bulgaria, Poland, other Slavic countries,[3] as well as in France, Belgium, Finland,[4] Romania, Germany and Hungary.[5][failed verification]

Automotive and transportation

  • 7 (New York City Subway service), a service of the New York City Subway
  • BMW 7 Series, a flagship range of luxury vehicles from German automobile manufacturer, BMW.
  • The Lotus Seven, a sports car produced by Lotus
  • Each airplane in Boeing's line of passenger jets is named with a 3-digit number beginning and ending in 7.

Classical world

Classical antiquity

Commerce and business

  • 7-Eleven is the trading name of a chain of convenience stores based in the U.S.
  • Seven Jeans, also known as Seven '7' for all Mankind, a brand of designer jeans.

Food and beverages

  • 7 Up is the name of a popular soft drink.

Media and entertainment

Film

Characters

Titles

Films

Games

  • Lotto Super 7, a Canadian-lottery game that had its final drawing September 18, 2009.
  • Sevens, a card game
  • Seven is the sum of any two opposite sides on a standard six-sided dice.
  • In the game of craps, a dice roll of 7 on the come-out constitutes a “natural” and the Pass line wins immediately. However, if the shooter (dice thrower) rolls a 4, 5, 6, 8, 9, or 10 on the come-out roll, that number becomes his “point”. Now, the shooter must repeat his point before he throws a seven. If he repeats his point, the Pass line wins. If he rolls a seven, not only does the Pass line lose, the shooter loses control of the dice. This is called a “seven-out”.

Video games

  • The 7th Guest, produced by Trilobyte and released by Virgin Games in 1993, is an FMV-based puzzle horror video game.
  • "The 7" are a group of deadly mercenaries that kidnap the protagonist's family in the video game Kane & Lynch: Dead Men.
  • In the Killer7 game, the number of individual personalities serving Harman Smith as part of the group of assassins called the Killer7
  • In 999: Nine Hours, Nine Persons, Nine Doors, one of the characters goes by the code name "Seven".
  • In the Fallen London story Seeking Mr. Eaten's Name, the number 7 is a recurring theme.
  • Mario Kart 7, published by Nintendo and developed by Retro Studios, is a kart racing video game.

Literature

  • As You Like It by William Shakespeare's contains Shakespeare's 7 Ages of Man theory.
  • In Beloved, the novel by Toni Morrison, the number seven seems to have recurring significance, Beloved has seven letters, 124 adds up to seven, each chapter begins on a number containing seven, and the second chapter contains seven parts.
  • The original British version of Anthony Burgess' novel A Clockwork Orange is split into three sections of seven chapters.
  • In the first of the three Deltora Quest series of books by Emily Rodda, the protagonist must collect the seven gems of the fabled Belt of Deltora: topaz, ruby, opal, lapis lazuli, emerald, amethyst, and diamond. Each of the seven gems are guarded by one of seven guardians located in one of the seven locations around Deltora: The Forests of Silence, Lake of Tears, City of the Rats, The Shifting Sands, Dread Mountain, Maze of the Beast, and Valley of the Lost.
  • In the Dragon Ball series, there are 7 crystalline spheres known as the Dragon balls. Each Dragon ball has a certain number of stars on it displaying its respective number in the set.
  • The manga Eureka Seven, based on the anime series
  • In Fist of the North Star (Hokuto no Ken), the main character, Kenshiro, is also known as "the man with seven wounds" for the seven scars on his body in the shape of the Big Dipper.
  • In the Fushigi Yuugi manga series, the four beast gods each have seven warriors, the Genbu Seven, the Byakko Seven, the Seiryuu Seven, and the Suzaku Seven.
  • In the Harry Potter series of novels by J.K. Rowling, seven is said to be the most powerfully magical number. There are a number of references to seven in Harry Potter: there are a total of seven books in the series; Ginny Weasley is the seventh child and only daughter of the Weasley family; Harry Potter was born in July, the seventh month of the year; Wizarding students must complete seven years of school at Hogwarts; There are seven secret passages leading out of Hogwarts; Seven is also the number on the back of Harry Potter's Quidditch robes (Prisoner of Azkaban movie). Professor Moody was also hidden in a chest with an underground cubby, which was locked with seven locks Harry Potter and the Goblet of Fire. In Quidditch each team consists of seven players. Chapter four of Book 7 is titled "The Seven Potters". Lord Voldemort planned on making six Horcruxes (objects containing parts of his soul), so that his soul would exist in seven parts, but made an extra one, making a total of seven Horcruxes.
  • In the InuYasha series, the Shichinintai are, as their name says, a band of seven mercenaries.
  • The Seven Rings of the Vongola Family in Katekyo Hitman Reborn: Sky, Storm, Rain, Sun, Thunder, Mist, and Cloud.
  • In The Lost Years of Merlin series, a book is titled "The Seven Songs of Merlin"
  • The character 7 (Nana) and the organization Septimal Moon in Loveless (manga)
  • In the "Nana manga series, there are many recurrent instances of the number seven ("nana" is Japanese for "seven"), including the name of both main characters.
  • Team 7 consists of the main characters in Naruto: Naruto Uzumaki, Sasuke Uchiha, Kakashi Hatake, and Sakura Haruno. Later in the series, Sai joined team 7 after Sasuke left Konohagakure.
  • One of the Tailed Beasts, in the unnamed Naruto universe, which is the Seven-Tailed beast, and a giant Kabutomushi, was revealed to be named Chōmei, and the jinchuriki host to the young kunoichi Fū. Has six dragonfly like wings that makes up six of its tails, and a long stem that also makes up its actual tail.
  • In the One Piece series, the Shichibukai (literally, "Seven Military Seas", known in the English versions as the "Seven Warlords of the Sea") are seven powerful pirates who work for the government.
  • The Saga of Seven Suns, a series of seven novels by Kevin J. Anderson.
  • In Neil Gaiman's Sandman series, there are 7 Endless: Destiny, Death, Dream, Destruction, Despair, Desire and Delirium.
  • The Secret Seven, name of a children's adventure book by Enid Blyton
  • In the Septimus Heap series, Septimus Is the seventh son of a seventh son, 7 is believed to be the most magykal number. There will also be 7 books in the series, along with many other things relating to the number 7.
  • Aleksis Kivi's "Seven Brothers", the most famous book of Finnish literature
  • The Seven Dials Mystery by Agatha Christie
  • The Seven Habits of Highly Effective People, a book by Stephen Covey
  • Seven Pillars of Wisdom, a book written by T.E. Lawrence
  • The book Seven Years in Tibet
  • The novel Seven Days in May, written by Fletcher Knebel
  • In The Silmarillion, also a Tolkien work, there are seven Lords of the Valar, and seven Ladies of the Valar; Fëanor, a central character, has seven sons: Maedhros, Maglor, Celegorm, Curufin, Caranthir, Amrod, and Amras.
  • In George R.R. Martin's A Song of Ice and Fire, seven gods, the Mother, the Father, the Warrior, the Crone, the Smith, the Maiden, and the Stranger, are worshipped in the land of Westeros, which is made up of seven former kingdoms and often called the Seven Kingdoms. The Seven are the primary deities of Westeros.
  • In W. E. B. Du Bois's book The Souls of Black Folk, he refers to "the Negro" as "the seventh son".
  • In The Tales of Alvin Maker, an alternate history fantasy series by Orson Scott Card, seventh sons are imbued with special powers, referred to as "knacks", over the physical world. The powers of a seventh son of a seventh son, the birthright of the series' main character, Alvin Smith, are especially pronounced. Men who wield these powers to create are referred to as "Makers."
  • In Toaru Majutsu no Index, there are a total of seven Level 5 espers: Accelerator, Kakine Teitoku, Misaka Mikoto, Mugino Shizuri, Shokuhou Misaki, an unknown esper and Sogiita Gunha.
  • In The Two Towers, the second volume of J. R. R. Tolkien's The Lord of the Rings, the following poem appears: "Tall ships and tall kings/Three times three/What brought they from the foundered land/Over the flowing sea?/Seven stars and seven stones/And one white tree." The "foundered land" is Númenor, and the "Seven Stars" are unknown, but they may refer to a constellation, the Sickle of the Valar. The Seven Stones are the palantíri, the seeing-stones. The number seven was also significant to Dwarvish culture as portrayed by Tolkien: there were seven fathers of the Dwarves (as recounted in The Silmarillion) and the Dwarves were later given seven rings by Sauron (according to The Lord of the Rings).
  • David Eastis authored two books about the popular number seven both with the title "7".
  • Jackie Leo wrote "Seven".
  • We are Seven by William Wordsworth
  • In The Owl Keeper]], the owl keeper (by Christine Brodien-Jones) is said to be born on the 7th day of the 7th month at 7 past midnight.
  • Marina or Number Seven is a character in the book series The Lorien Legacies.
  • The Revenge of Seven by Pittacus Lore
  • In Rick Riordan's series The Heroes of Olympus there are seven heroes of the Great Prophecy: Percy Jackson, Annabeth Chase, Jason Grace, Piper McLean, Leo Valdez, Hazel Levesque, and Frank Zhang.

Music

  • The number of notes in the traditional Western diatonic scale (major or minor)
  • In music, the Roman numeral vii is the leading tone (vii°) or subtonic (VII) scale degree, chord (leading-tone seventh chord or secondary leading-tone chord), or diatonic function, when distinguished V = major and v = minor.
  • The original diameter in inches of the 45rpm format gramophone record.
  • There are seven musicians in a septet or a septuor.
  • There are seven basic swaras [saptaswaras] in Indian Carnatic music
  • "7" is a song by Prince and The New Power Generation, from the 1992 Love Symbol Album.
  • 7 is a 2003 Enrique Iglesias album.
  • 7 (Mick Thompson) is one of the guitarists for popular metal band Slipknot.
  • Sweet 7 is an album by Sugababes
  • The number of dastgahs in Persian traditional music
  • 'Seventh son of a Seventh son' is the 7th album of the English heavy metal band Iron Maiden, brought out in 1988
  • Sevens is the 7th album by Country singer Garth Brooks, released in 1997, consisting of 14 songs(2 sets of 7).
  • "Seven" is a song by Megadeth on their 1999 album Risk
  • UK-based alt-rock band, Take The Seven (TTVII).
  • "The Munificent Seven" is the appended parenthetical title for the song "Love Is Stronger Than Justice" on Sting's 1993 album Ten Summoner's Tales
  • Seven is a song on David Bowie's album Hours
  • Seven days is a song of Sting in his album 'Ten Summoner's Tales
  • Seven Swans is the name of the 2004 album by Sufjan Stevens.

Sports

Baseball
  • In high school baseball, a regulation game lasts seven innings.
  • In baseball, there are seven ways that a batter can reach base (safe hit, base on balls, fielder’s error, fielder’s choice, hit by pitch, catcher’s interference, and dropped third strike).
  • In baseball, the 7th Inning stretch attributed to the 27th U.S. President, William Howard Taft.
  • In scoring baseball, seven represents the left fielder's position.
Football and soccer
Frisbee and Ultimate Frisbee
Handball
Motor sports
Rugby
Rugby league
  • The jersey number 7 is worn by the starting scrum-half/halfback in most competitions (but not in the European Super League, which uses static squad numbering).
  • 7, The number of consecutive State of Origin Series wins (2006-2012) by Queensland against New South Wales in Australia. The highest since the inception of the State of Origin Series concept which commenced in 1980.
Rugby union
  • The jersey number 7 is worn by the starting openside flanker. (Some teams use "left" and "right" flankers instead of "openside" and "blindside", with 7 being worn by the starting right flanker.)
  • A converted try is worth 7 points. This number is also significant because the standard bonus points system used in most competitions awards 1 bonus point to a team that loses by 7 points or less.
  • The IRB Sevens World Series, an annual competition for national teams in rugby union sevens (see below)
  • The Rugby World Cup Sevens, the World Cup for the union version of Sevens
Cross-code
  • Rugby sevens, a variant of union and league that contains only seven players per side instead of the standard 15 (union) or 13 (league)
Softball
  • A regulation game in softball consists of seven innings.
Track and field
Water polo
  • Each team is allowed to have a maximum of seven players, one of them a goalkeeper, in the playing area of the pool at any given time.

Television

Networks and stations

  • The circle 7 logo used by numerous ABC network O&O stations in the U.S. (In the late 1940s, ABC arranged for its five original, founding O&O TV stations to broadcast on channel 7.)
  • Maximum number of VHF broadcast channels available in any TV market in the United States of America; they are channels 2, 4, 5, 7, 9, 11, and 13 in the Greater New York City and Los Angeles-Long Beach SMSAs.
  • ProSieben (sieben being German for seven), a television network in Germany
  • Seven Network, a television network in Australia.
  • Trans7 (formerly TV7 before taken over by Trans Corporation), a television network in Indonesia.
  • GMA 7 (DZBB-TV channel 7 In Metro Manila) a television network in the Philippines.

Programs

  • 7 Days, a comedy gameshow based on news stories from New Zealand.
  • The name of a television show 7th Heaven.
  • The name of a The Adventures of Super Mario Bros. 3 cartoon episode, "7 Continents for 7 Koopas".
  • Blake's 7 was a BBC science fiction series that ran from 1978 to 1981
  • Eureka Seven, a science fiction and romance anime.
  • In Red Dwarf II episode "Parallel Universe", Holly forgets the number 7 in a countdown for the Holly Hop Drive. After Rimmer reminds him, he admits he has "a blind spot for sevens".
  • Seven, an episodic character from the sitcom Married... with Children.
  • In the Seinfeld episode "The Seven", Seven is the name George Costanza desires to give his first-born, having allegedly promised this to the widow of baseball great Mickey Mantle (whose uniform number was 7). George is enraged, however, when his fiance's cousin and spouse copy the idea and give the name to their child.
  • Seven Days, a science fiction show about the NSA using time travel.
  • The name of one of the monsters in the cartoon television show Seven Little Monsters.
  • In Star Trek: Voyager, Seven of Nine (also called Seven for short) is one of the crewmembers
  • The Ultra Series has two heroes with "Seven" in their name: Ultra Seven and Ultra Seven-21.
  • Ultra Seven, a television series aired in 1967, and the superhero of the same name. He is the honorary seventh member of the Ultra Garrison
  • In House of Anubis (on Nickelodeon), the "chosen one" has to be born on 7/7 (July 7) at 7:00am.
  • George Carlin in what is perhaps his best-known routine, "Seven Words You Can Never Say on Television".
  • Lucky 7: Short-lived ABC TV series (premiered 2013) about seven people who win the lottery.
  • The last episode of American Horror Story: Coven is named The Seven Wonders, after the seven great powers a witch should perform to become the leader or "Supreme" of the generation: Telekinesis, Concilium, Descensum, Divination, Transmutation, Vitalum Vitalis and Pyrokinesis.
  • In the anime series Yu-Gi-Oh! Duel Monsters, there are seven magical ancient Egyptian artefacts, known as the Millenium Items (Puzzle, Eye, Ring, Key, Scale, Rod and Necklace), which play a significant role in the storyline of the show throughout its duration.
  • The number 7 is the racing number of Herbie's girlfriend, Giselle, in the movie Herbie Goes to Monte Carlo

Places

  • The traditional count of Basque provinces as expressed in the slogan Zazpiak Bat, translates as "the seven [are] one" and refers to the seven Basque traditional provinces..
  • The figurative number of seas
  • The Seven Virgins mountain range in Sri Lanka, which was the scene of an air disaster on December 4, 1974, involving a DC-8 Series 55F passenger jetliner operated by the charter company Martinair, which left 191 dead.
  • The Sevens (sometimes typeset as "7he Sevens"), a rugby union stadium in Dubai, UAE and home to the Dubai Sevens tournament

Religion and mythology

Old Testament

  • Seven Hebrew words of Bereishit 1:1 / Genesis 1:1 (28 letters).
Seven Days of Creation - 1765 book

The number seven in the seven days of Creation is typological and the number seven appears commonly elsewhere in the Bible. These include:

  • Seven days of Creation (Genesis 1) e.g., God rested on and sanctified the seventh day (Sabbath)
  • Anyone who dares to kill Cain 'will suffer vengeance seven times over' (Genesis 4:15)
  • Lamech in his "Song of the Sword" claims that 'if Cain shall be avenged sevenfold', he himself shall be 'seventy-sevenfold' (Genesis 4:24)
  • Noah is commanded to bring seven pairs of every clean animal onto the ark (Genesis 7:2)
  • Seven years of plenty and seven years of famine in Pharaoh's dream (Genesis 41)
  • In regards to the sin sacrifice, the anointed priest was to sprinkle the bullock's blood seven times before the lord (Leviticus 4:6)
  • Seven days of the feast of Passover (Exodus 13:3–10)
  • Seven-day week and the pattern concerning distribution and use of manna (Exodus 16)
  • The Menorah (Hebrew: מנורה), is a seven-branched candelabrum lit by olive oil in the Tabernacle and the Temple in Jerusalem (Exodus 25)
  • Seven year cycle around the years of Jubilee (Leviticus 25)
  • Jericho's walls fall on the seventh day after seven priests with seven trumpets march around the city seven times (Joshua 6:8)
  • King David had seven older brothers (1 Samuel 16)
  • The child sneezed seven times after Elisha raised him from the dead (2 Kings 4:35)
  • Seven things that are detestable to the LORD (Proverbs 6:16–19)
  • Seven Pillars of the House of Wisdom (Proverbs 9:1)
  • The woman with seven sons in 2 Maccabees.

New Testament

  • Seven loaves multiplied into seven basketfuls of surplus (Matthew 15:32–37)
  • Peter asked Jesus if he should forgive those who sinned against him up to 7 times; Jesus responded by saying to forgive them 'seventy times seven times', remembering so the curse of Cain and the song of Lamech in Genesis 4.[7]
  • Seven demons were driven out of Mary Magdelene. (Luke 8:2).
  • The seven last sayings of Jesus on the cross.
  • Seven men of honest report, full of the Holy Ghost and wisdom (Acts 6:3)
  • In the Book of Revelation, seven is a central figure of quantities: Seven Spirits of God, Seven Churches (to which the book is addressed);
  • Seven of the following appear in Revelation: golden lampstands(1:12), stars(1:16), torches of fire(4:5) Seven Seals(5:1), angels and their trumpets(8:2), last plagues(15:1), golden bowls(15:7), thunders(10:3), horns and eyes(5:6), diadems(12:3) and kings(17:10). See Category:Seven in the Book of Revelation.

Other sevens in Christian knowledge and practice include:

Hinduism

  • The Sanskrit word sapta refers to number seven.
  • Indian Music has "Saptak Swaras," seven octats (sa re ga ma pa dha ni) which are basics of music, using which hundreds of Ragas are composed.
  • Celestial group of seven stars (7 Classical Planets) are named as "Sapta Rishi" based on the seven great saints.
  • Seven Promises [Saptapadi], Seven Rounds in Hindu Wedding and Seven Reincarnation
  • According to Hinduism, there are seven worlds in the universe, seven seas in the world and seven Rishies (seven gurus) called sapta rishis.
  • Seven hills at tirumala also known as Yedu Kondalavadu [in Telugu], ezhu malaiyan [in Tamil] means Sevenhills God
  • There are 7 Chakras in the basic model used in various eastern traditions and philosophies.

Islam

  • The number of ayat in surat al-Fatiha
  • The number of layers of the Earth in Islamic religion is seven
  • The number of skies in Islamic religion is seven
  • The number of circumambulations (Tawaf) that are made around the Kaaba
  • The number of walks between Al-Safa and Al-Marwah mountains—that is travelling back and forth—seven times during the ritual pilgrimages of Hajj and Umrah
  • The number of heavens in Islamic religion, i.e. levels in heaven.
  • The number of hells in hell is also seven i.e. levels in hell.
  • The number of doors to hell is seven (for heaven the number of doors is eight).
  • In Verse 12:46 (see Islamic view of Joseph) of the Quran, Joseph (Yusef) is asked to interpret the King's dream where seven fat cows were dreamt to have been devoured by seven skinny cows and seven green spikes, and others shrivelled.
  • The number of the big sins or vices is seven which are from a Hadith of the prophet Mohamed : "Avoid the seven sins polytheism, witchcraft, the killing of the soul which Allah has forbidden except by right, consuming riba, consuming the wealth of the orphan, to escape from the battles and slandering chaste women"
  • A naming ceremony is held for babies on their seventh day of life

Judaism

  • Shiv`a (another pronunciation of the Hebrew word for 7—(Hebrew: שבעה, "seven")), is the number of days of mourning. Hence, one sits Shiva. As in Shiva (Judaism)
  • The weekly Torah portion is divided into seven aliyahs, and seven Jewish men (or boys over the age of 13 who are considered men; Bar Mitzvah) are called up for the reading of these aliyahs during Shabbat morning services.
  • Seven blessings are recited under the chuppah during a Jewish wedding ceremony.
  • A Jewish bride and groom are feted with seven days of festive meals after their wedding, known as Sheva Berachot ("Seven Blessings").
  • The number of Ushpizzin (also known as the "Seven Shepherds") who visit the sukkah during the holiday of Sukkot: Abraham, Isaac, Jacob, Joseph, Moses, Aaron, and David.
  • The number of nations God told the Israelites they would displace when they entered the land of Israel (Deut. 7:1): the Hittite, the Girgashite, the Amorite, the Canaanite, the Perizzite, the Hivite, and the Jebusite.
  • In Breslov tradition, the seven orifices of the face (2 eyes, 2 nostrils, 2 ears, and the mouth) are called "The Seven Candles."
  • The 7 Sephirot of primary conscious emotion that are attributes of the creator.
  1. Golden Star
  2. White Clouds
  3. Blue (Heaven) Sky
  4. B-lack (of Colors) Moon Empty Infinity Space / Earth (where grown Trees).
  5. Green Wood
  6. Red (Hell) Fire

Astrology

  • The number of daughters of Atlas in the Pleiades (also called the "Seven Sisters")
  • The number of saints appearing in a constellation called "Saptharishi Mandalam" in Indian astronomy.

Others

Deity, being, or character
The Seven Lucky Gods in Japanese mythology
  • The Seven Lucky Gods refer to the seven gods of good fortune in Japanese mythology.
  • The number of archangels according to some systems.
  • In Buddhism, Buddha walked 7 steps at his birth.
  • In Khasi mythology, the seven divine women who were left behind on earth and became the ancestresses of all humankind.
  • The number of sleeping men in the Christian myth of the "Seven Sleepers."
  • The number of sages in Hindu mythology; their wives are the deities referred to as the Sapta Matrka or "Seven Mothers"
  • In Iran,[9] German, Spanish, and other cultures that speak Romance Languages, cats are said to have 7 lives as opposed to English, where cats are said to have 9 lives.
  • In Irish mythology, the epic hero Cúchulainn is associated with the number 7. He has 7 fingers on each hand, 7 toes on each foot, and 7 pupils in each eye. In the Irish epic Táin Bó Cúailnge, Cúchulainn is 7 years old when he receives his first weapons and defeats the armies of the Ulaidh and his son Connla is 7 years old when he is slain by Cúchulainn in "The Death of Aife's Only Son."
  • In Galician folklore, a seventh son will be a werewolf. In other folklores, after six daughters, the seventh child is to be a son and a werewolf. In other European folklores, the seventh son of a seventh son will be a child with special powers of healing and clairvoyant seeing, and in other cultures that seventh son of a seventh son would be a vampire.
  • In Guaraní mythology, the number of prominent legendary monsters.
  • In the eponymous British folk tale, Thomas the Rhymer went to live in the faerie kingdom for 7 years.
  • Mahatma Gandhi's list of the destructive Seven Blunders of the World that cause violence: Wealth without work, pleasure without conscience, knowledge without character, commerce without morality, science without humanity, religion without sacrifice and politics without principle.
  • The cosmogony of Urantia[10] gives an explanation to the sacredness of the number 7 in some religions, including those based on a triple deity: 7 indeed is the number of all the possible combinations of three elements taken one by one, two by two, or by three. It therefore expresses all the associative possibilities of the three fundamental aspects of the absolute (Christian Trinity, for example, or Trimurti in Hinduism) which organizes the Creation. The seventh of these combinations being the one that combines the three aspects, 7 therefore also expresses spiritual achievement.
  • In other traditions and teachings, seven is seen as the perfect number that holds creation and the universe together.[11] From the 7 deadly sins to 7 chakras, 7 heavens and 7 planes of creation, this number holds great significance.
Place
  • The number of main islands of mythological Atlantis.
  • The number of gateways traversed by Inanna during her descent into the underworld.
  • Cibola was one of the legendary Seven Cities of Gold the Spanish thought existed.
  • In the Bahá'í faith, the text The Seven Valleys, by the Prophet-Founder Bahá'u'lláh, relates the journey of the soul through the seven "valleys" of Search, Love, Knowledge, Unity, Contentment, Wonderment, and finally True Poverty and Absolute Nothingness.
Scripture
Thing, concept, or symbol
Time

Science

Astronomy

Biology

Chemistry

Heptane is an alkane with 7 carbon atoms per molecule

The periodic table has 7 rows of known elements

  • The number of periods, or horizontal rows of elements, in the periodic table
  • The number of principal energy levels for electrons around the nucleus
  • The number of crystal systems: triclinic, monoclinic, orthorhombic, tetragonal, trigonal, hexagonal, and cubic.
  • The number of crystal lattice systems: cubic (or isometric), hexagonal, tetragonal, rhombohedral, orthorhombic, monoclinic and triclinic.

Physics

Isaac Newton's 7 colors of the rainbow

Psychology

Software

Temporal, seasonal and holidays

See also

Notes

  1. ^ Georges Ifrah, The Universal History of Numbers: From Prehistory to the Invention of the Computer transl. David Bellos et al. London: The Harvill Press (1998): 395, Fig. 24.67
  2. ^ Eeva Törmänen (September 8, 2011). "Aamulehti: Opetushallitus harkitsee numero 7 viivan palauttamista". Tekniikka & Talous (in Finnish).
  3. ^ "Education writing numerals in grade 1."(Russian)
  4. ^ Elli Harju (August 6, 2015). ""Nenosen seiska" teki paluun: Tiesitkö, mistä poikkiviiva on peräisin?". Iltalehti (in Finnish).
  5. ^ "Example of teaching materials for pre-schoolers"(French)
  6. ^ Mark, Joshua. "Pharaoh". Ancient History Encyclopedia. Retrieved 25 January 2017.
  7. ^ 21Then Peter came to Jesus and asked, 'Lord, how many times shall I forgive my brother when he sins against me? Up to seven times?' 22Jesus answered, 'I tell you, not seven times, but seventy times seven.'
  8. ^ "Sermon Illustrations". Bible.org. Retrieved 2012-09-07.
  9. ^ "''Encyclopædia Britannica'' "Number Symbolism"". Britannica.com. Retrieved 2012-09-07.
  10. ^ Urantia Fondation website
  11. ^ Nunitus, Septem (2016). 777: Messages from the Elder Gods (777 Series Book 1). Elder Gods Press. p. 5. ASIN B01I0EUQGA
  12. ^ Bellos, Alex (8 April 2014). "'Seven' triumphs in poll to discover world's favourite number". The Guardian. Retrieved 9 February 2017.
  13. ^ "Is seven your favorite number? We thought so. Here's what it says about you". Public Radio International. 2014-04-08. Retrieved 9 February 2017.
  14. ^ "SI brochure, The seven SI base units". Retrieved 2009-09-11.
  15. ^ "SI brochure, SI derived units". Retrieved 2009-09-11.

References