# Mersenne prime

Named after Marin Mersenne 1536[1] Regius, H. 48 Infinite Mersenne numbers 3, 7, 31, 127 257885161 − 1 (January 2013) A000668

In mathematics, a Mersenne prime is a prime number of the form $M_n=2^n-1$. They are named after the French monk Marin Mersenne who studied them in the early 17th century.

It is easy to see that if n is a composite number then so is 2n − 1. The definition is therefore unchanged when written $M_p=2^p-1$ where p is assumed prime.

More generally, numbers of the form $M_n=2^n-1\,$ without the primality requirement are called Mersenne numbers. Mersenne numbers are sometimes defined to have the additional requirement that n be prime, equivalently that they be pernicious Mersenne numbers, namely those pernicious numbers whose binary representation contains no zeros. The smallest composite pernicious Mersenne number arises with p = 11.

As of February 2013, 48 Mersenne primes are known. The largest known prime number (257,885,161 − 1) is a Mersenne prime.[2][3] Since 1997, all newly-found Mersenne primes have been discovered by the “Great Internet Mersenne Prime Search” (GIMPS), a distributed computing project on the Internet.

 Are there infinitely many Mersenne primes?

Many fundamental questions about Mersenne primes remain unresolved. It is not even known whether the set of Mersenne primes is finite. The Lenstra–Pomerance–Wagstaff conjecture asserts that there are infinitely many Mersenne primes and predicts their order of growth. It is also not known whether infinitely many Mersenne numbers with prime exponents are composite, although this would follow from widely believed conjectures about prime numbers, for example, the infinitude of Sophie Germain primes congruent to 3 (mod 4).

The first four Mersenne primes are

M2 = 3, M3 = 7, M5 = 31 and M7 = 127.

A basic theorem about Mersenne numbers states that if Mp is prime, then the exponent p must also be prime. This follows from the identity

\begin{align}2^{ab}-1&=(2^a-1)\cdot \left(1+2^a+2^{2a}+2^{3a}+\cdots+2^{(b-1)a}\right)\\&=(2^b-1)\cdot \left(1+2^b+2^{2b}+2^{3b}+\cdots+2^{(a-1)b}\right).\end{align}

This rules out primality for Mersenne numbers with composite exponent, such as M4 = 24 − 1 = 15 = 3×5 = (22 − 1)×(1 + 22).

Though it was believed by early mathematicians that Mp is prime for all primes p, Mp is very rarely prime. In fact, of the 1,622,441 prime numbers p up to 25,964,951,[4] Mp is prime for only 42 of them. The smallest counterexample is the Mersenne number

M11 = 211 − 1 = 2047 = 23 × 89.

The lack of any simple test to determine whether a given Mersenne number is prime makes the search for Mersenne primes a difficult task, since Mersenne numbers grow very rapidly. The Lucas–Lehmer primality test (LLT) is an efficient primality test that greatly aids this task. The search for the largest known prime has somewhat of a cult following. Consequently, a lot of computer power has been expended searching for new Mersenne primes, much of which is now done using distributed computing.

Mersenne primes are used in pseudorandom number generators such as the Mersenne twister, Park–Miller random number generator, Generalized Shift Register and Fibonacci RNG.

## Perfect numbers

Mersenne primes Mp are also noteworthy due to their connection to perfect numbers. In the 4th century BC, Euclid proved that if 2p−1 is prime, then 2p−1(2p−1) is a perfect number. This number, also expressible as Mp(Mp+1)/2, is the Mpth triangular number and the 2p−1th hexagonal number. In the 18th century, Leonhard Euler proved that, conversely, all even perfect numbers have this form.[5] It is unknown whether there are any odd perfect numbers.

## History

Mersenne primes take their name from the 17th-century French scholar Marin Mersenne, who compiled what was supposed to be a list of Mersenne primes with exponents up to 257. His list was largely incorrect, as Mersenne mistakenly included M67 and M257 (which are composite), and omitted M61, M89, and M107 (which are prime). Mersenne gave little indication how he came up with his list.[6]

Édouard Lucas proved in 1876 that M127 is indeed prime, as Mersenne claimed. This was the largest known prime number for 75 years, and the largest ever calculated by hand. M61 was determined to be prime in 1883 by Ivan Mikheevich Pervushin, though Mersenne claimed it was composite, and for this reason it is sometimes called Pervushin's number. This was the second-largest known prime number, and it remained so until 1911. Lucas had shown another error in Mersenne's list in 1876. Without finding a factor, Lucas demonstrated that M67 is actually composite. No factor was found until a famous talk by Cole in 1903. Without speaking a word, he went to a blackboard and raised 2 to the 67th power, then subtracted one. On the other side of the board, he multiplied 193,707,721 × 761,838,257,287 and got the same number, then returned to his seat (to applause) without speaking.[7] A correct list of all Mersenne primes in this number range was completed and rigorously verified only about three centuries after Mersenne published his list.

## Searching for Mersenne primes

Fast algorithms for finding Mersenne primes are available, and as of 2013 the ten largest known prime numbers are Mersenne primes.

The first four Mersenne primes M2 = 3, M3 = 7, M5 = 31 and M7 = 127 were known in antiquity. The fifth, M13 = 8191, was discovered anonymously before 1461; the next two (M17 and M19) were found by Cataldi in 1588. After nearly two centuries, M31 was verified to be prime by Euler in 1772. The next (in historical, not numerical order) was M127, found by Lucas in 1876, then M61 by Pervushin in 1883. Two more (M89 and M107) were found early in the 20th century, by Powers in 1911 and 1914, respectively.

The best method presently known for testing the primality of Mersenne numbers is the Lucas–Lehmer primality test. Specifically, it can be shown that for prime p > 2, Mp = 2p − 1 is prime if and only if Mp divides Sp−2, where S0 = 4 and, for k > 0,

$S_k = S_{k-1}^2-2.\$
Graph of number of digits in largest known Mersenne prime by year – electronic era. Note that the vertical scale, the number of digits, is a double logarithmic scale of the value of the prime.

The search for Mersenne primes was revolutionized by the introduction of the electronic digital computer. Alan Turing searched for them on the Manchester Mark 1 in 1949,[8] but the first successful identification of a Mersenne prime, M521, by this means was achieved at 10:00 pm on January 30, 1952 using the U.S. National Bureau of Standards Western Automatic Computer (SWAC) at the Institute for Numerical Analysis at the University of California, Los Angeles, under the direction of Lehmer, with a computer search program written and run by Prof. R.M. Robinson. It was the first Mersenne prime to be identified in thirty-eight years; the next one, M607, was found by the computer a little less than two hours later. Three more — M1279, M2203, M2281 — were found by the same program in the next several months. M4253 is the first Mersenne prime that is titanic, M44497 is the first gigantic, and M6,972,593 was the first megaprime to be discovered, being a prime with at least 1,000,000 digits.[9] All three were the first known prime of any kind of that size.

In September 2008, mathematicians at UCLA participating in GIMPS won part of a $100,000 prize from the Electronic Frontier Foundation for their discovery of a very nearly 13-million-digit Mersenne prime. The prize, finally confirmed in October 2009, is for the first known prime with at least 10 million digits. The prime was found on a Dell OptiPlex 745 on August 23, 2008. This is the eighth Mersenne prime discovered at UCLA.[10] On April 12, 2009, a GIMPS server log reported that a 47th Mersenne prime had possibly been found. This report was apparently overlooked until June 4, 2009. The find was verified on June 12, 2009. The prime is 242,643,801−1. Although it is chronologically the 47th Mersenne prime to be discovered, it is smaller than the largest known at the time, which was the 45th to be discovered. On January 25, 2013, Curtis Cooper, a mathematician at the University of Central Missouri, discovered a 48th Mersenne prime, 257,885,161−1 (a number with 17,425,170 digits), as a result of a search executed by a GIMPS server network.[11] This was the third Mersenne prime discovered by Dr. Cooper and his team in the past seven years. ## Theorems about Mersenne numbers 1. If a and p are natural numbers such that ap − 1 is prime, then a = 2 or p = 1. • Proof: a ≡ 1 (mod a − 1). Then ap ≡ 1 (mod a − 1), so ap − 1 ≡ 0 (mod a − 1). Thus a − 1 | ap − 1. However, ap − 1 is prime, so a − 1 = ap − 1 or a − 1 = ±1. In the former case, a = ap, hence a = 0,1 (which is a contradiction, as neither 1 nor 0 is prime) or p = 1. In the latter case, a = 2 or a = 0. If a = 0, however, 0p − 1 = 0 − 1 = −1 which is not prime. Therefore, a = 2. 2. If 2p - 1 is prime, then p is prime. • Proof: suppose that p is composite, hence can be written p = ab with a and b > 1. Then (2a)b − 1 is prime, but b > 1 and 2a > 2, contradicting statement 1. 3. If p is an odd prime, then any prime q that divides 2p − 1 must be 1 plus a multiple of 2p. This holds even when 2p − 1 is prime. • Examples: Example I: 25 − 1 = 31 is prime, and 31 = 1 + 3×2×5. Example II: 211 − 1 = 23×89, where 23 = 1 + 2×11, and 89 = 1 + 4×2×11. • Proof: If q divides 2p − 1 then 2p ≡ 1 (mod q). By Fermat's Little Theorem, 2(q − 1) ≡ 1 (mod q). Assume p and q − 1 are relatively prime, a similar application of Fermat's Little Theorem says that (q − 1)(p − 1) ≡ 1 (mod p). Thus there is a number x ≡ (q − 1)(p − 2) for which (q − 1)·x ≡ 1 (mod p), and therefore a number k for which (q − 1)·x − 1 = kp. Since 2(q − 1) ≡ 1 (mod q), raising both sides of the congruence to the power x gives 2(q − 1)x ≡ 1, and since 2p ≡ 1 (mod q), raising both sides of the congruence to the power k gives 2kp ≡ 1. Thus 2(q − 1)x/2kp = 2(q − 1)x − kp ≡ 1 (mod q). But by definition, (q − 1)x − kp = 1, implying that 21 ≡ 1 (mod q); in other words, that q divides 1. Thus the initial assumption that p and q − 1 are relatively prime is untenable. Since p is prime q − 1 must be a multiple of p. Of course, if the number m = (q − 1)p is odd, then q will be even, since it is equal to mp + 1. But q is prime and cannot be equal to 2; therefore, m is even. • Note: This fact provides a proof of the infinitude of primes distinct from Euclid's Theorem: if there were finitely many primes, with p being the largest, we reach an immediate contradiction since all primes dividing 2p − 1 must be larger than p. 4. If p is an odd prime, then any prime q that divides $2^p-1$ must be congruent to ±1 (mod 8). • Proof: $2^{p+1} = 2 \pmod q$, so $2^{(p+1)/2}$ is a square root of 2 modulo $q$. By quadratic reciprocity, any prime modulo which 2 has a square root is congruent to ±1 (mod 8). 5. A Mersenne prime cannot be a Wieferich prime. • Proof: We show if p = 2m - 1 is a Mersenne prime, then the congruence 2p - 1 ≡ 1 does not satisfy. By Fermat's Little theorem, $m |p-1$. Now write, $p-1=m\lambda$. If the given congruence satisfies, then $p^2|2^{m\lambda}-1$,therefore 0 ≡ (2mλ - 1)/(2m - 1) = 1 + 2m + 22m + ... + 2λ-1m ≡ -λ mod(2m - 1}. Hence $2^m-1|\lambda$,and therefore λ ≥ 2m − 1. This leads to p − 1 ≥ m(2m − 1), which is impossible since m ≥ 2. 6. A prime number divides at most one prime-exponent Mersenne number[12] 7. If p and 2p+1 are both prime (meaning that p is a Sophie Germain prime), and p is congruent to 3 (mod 4), then 2p+1 divides 2p − 1.[13] • Example: 11 and 23 are both prime, and 11 = 2×4+3, so 23 divides 211 − 1. 8. All composite divisors of prime-exponent Mersenne numbers pass the Fermat primality test for the base 2. 9. The number of digits in the decimal representation of $M_n$ equals $\lfloor n\cdot \log_{10}2\rfloor+1$, where $\lfloor x\rfloor$ denotes the floor function. ## List of known Mersenne primes The table below lists all known Mersenne primes (sequence A000668 in OEIS): # p Mp Mp digits Discovered Discoverer Method used 1 2 3 1 c. 430 BC Ancient Greek mathematicians[14] 2 3 7 1 c. 430 BC Ancient Greek mathematicians[14] 3 5 31 2 c. 300 BC Ancient Greek mathematicians[15] 4 7 127 3 c. 300 BC Ancient Greek mathematicians[15] 5 13 8191 4 1456 Anonymous[16][17] Trial division 6 17 131071 6 1588[18] Pietro Cataldi Trial division[19] 7 19 524287 6 1588 Pietro Cataldi Trial division[20] 8 31 2147483647 10 1772 Leonhard Euler[21][22] Enhanced trial division[23] 9 61 2305843009213693951 19 1883 November[24] I. M. Pervushin Lucas sequences 10 89 618970019…449562111 27 1911 June[25] R. E. Powers Lucas sequences 11 107 162259276…010288127 33 1914 June 1[26][27][28] R. E. Powers[29] Lucas sequences 12 127 170141183…884105727 39 1876 January 10[30] Édouard Lucas Lucas sequences 13 521 686479766…115057151 157 1952 January 30[31] Raphael M. Robinson LLT / SWAC 14 607 531137992…031728127 183 1952 January 30[31] Raphael M. Robinson LLT / SWAC 15 1,279 104079321…168729087 386 1952 June 25[32] Raphael M. Robinson LLT / SWAC 16 2,203 147597991…697771007 664 1952 October 7[33] Raphael M. Robinson LLT / SWAC 17 2,281 446087557…132836351 687 1952 October 9[33] Raphael M. Robinson LLT / SWAC 18 3,217 259117086…909315071 969 1957 September 8[34] Hans Riesel LLT / BESK 19 4,253 190797007…350484991 1,281 1961 November 3[35][36] Alexander Hurwitz LLT / IBM 7090 20 4,423 285542542…608580607 1,332 1961 November 3[35][36] Alexander Hurwitz LLT / IBM 7090 21 9,689 478220278…225754111 2,917 1963 May 11[37] Donald B. Gillies LLT / ILLIAC II 22 9,941 346088282…789463551 2,993 1963 May 16[37] Donald B. Gillies LLT / ILLIAC II 23 11,213 281411201…696392191 3,376 1963 June 2[37] Donald B. Gillies LLT / ILLIAC II 24 19,937 431542479…968041471 6,002 1971 March 4[38] Bryant Tuckerman LLT / IBM 360/91 25 21,701 448679166…511882751 6,533 1978 October 30[39] Landon Curt Noll & Laura Nickel LLT / CDC Cyber 174 26 23,209 402874115…779264511 6,987 1979 February 9[40] Landon Curt Noll LLT / CDC Cyber 174 27 44,497 854509824…011228671 13,395 1979 April 8[41][42] Harry Lewis Nelson & David Slowinski LLT / Cray 1 28 86,243 536927995…433438207 25,962 1982 September 25 David Slowinski LLT / Cray 1 29 110,503 521928313…465515007 33,265 1988 January 29[43][44] Walter Colquitt & Luke Welsh LLT / NEC SX-2[45] 30 132,049 512740276…730061311 39,751 1983 September 19[46] David Slowinski LLT / Cray X-MP 31 216,091 746093103…815528447 65,050 1985 September 1[47][48] David Slowinski LLT / Cray X-MP/24 32 756,839 174135906…544677887 227,832 1992 February 17 David Slowinski & Paul Gage LLT / Maple on Harwell Lab Cray-2[49] 33 859,433 129498125…500142591 258,716 1994 January 4[50][51][52] David Slowinski & Paul Gage LLT / Cray C90 34 1,257,787 412245773…089366527 378,632 1996 September 3[53] David Slowinski & Paul Gage[54] LLT / Cray T94 35 1,398,269 814717564…451315711 420,921 1996 November 13 GIMPS / Joel Armengaud[55] LLT / Prime95 on 90 MHz Pentium PC 36 2,976,221 623340076…729201151 895,932 1997 August 24 GIMPS / Gordon Spence[56] LLT / Prime95 on 100 MHz Pentium PC 37 3,021,377 127411683…024694271 909,526 1998 January 27 GIMPS / Roland Clarkson[57] LLT / Prime95 on 200 MHz Pentium PC 38 6,972,593 437075744…924193791 2,098,960 1999 June 1 GIMPS / Nayan Hajratwala[58] LLT / Prime95 on 350 MHz Pentium II IBM Aptiva 39 13,466,917 924947738…256259071 4,053,946 2001 November 14 GIMPS / Michael Cameron[59] LLT / Prime95 on 800 MHz Athlon T-Bird 40 20,996,011 125976895…855682047 6,320,430 2003 November 17 GIMPS / Michael Shafer[60] LLT / Prime95 on 2 GHz Dell Dimension 41 24,036,583 299410429…733969407 7,235,733 2004 May 15 GIMPS / Josh Findley[61] LLT / Prime95 on 2.4 GHz Pentium 4 PC 42 25,964,951 122164630…577077247 7,816,230 2005 February 18 GIMPS / Martin Nowak[62] LLT / Prime95 on 2.4 GHz Pentium 4 PC 43[*] 30,402,457 315416475…652943871 9,152,052 2005 December 15 GIMPS / Curtis Cooper & Steven Boone[63] LLT / Prime95 on 2 GHz Pentium 4 PC 44[*] 32,582,657 124575026…053967871 9,808,358 2006 September 4 GIMPS / Curtis Cooper & Steven Boone[64] LLT / Prime95 on 3 GHz Pentium 4 PC 45[*] 37,156,667 202254406…308220927 11,185,272 2008 September 6 GIMPS / Hans-Michael Elvenich[65] LLT / Prime95 on 2.83 GHz Core 2 Duo PC 46[*] 42,643,801 169873516…562314751 12,837,064 2009 April 12[***] GIMPS / Odd M. Strindmo[66] LLT / Prime95 on 3 GHz Core 2 PC 47[*] 43,112,609 316470269…697152511 12,978,189 2008 August 23 GIMPS / Edson Smith[65] LLT / Prime95 on Dell Optiplex 745 48[**] 57,885,161 581887266…724285951 17,425,170 2013 January 25 GIMPS / Curtis Cooper[2] LLT / Prime95 on 3 GHz Core 2 Duo PC[67] ^ * It is not verified that no undiscovered Mersenne primes exist between the 42nd (M25,964,951) and the 47th (M43,112,609) on this chart; the ranking is therefore provisional. All Mersenne numbers in the interval have been tested at least once but some have not been double-checked.[68] ^ ** It is not known whether any undiscovered Mersenne primes exist between the 47th (M43,112,609) and the 48th (M57,885,161) on this chart; the ranking is therefore provisional. Some Mersenne numbers in the interval have not been tested.[68] Primes are not always discovered in increasing order. For example, the 29th Mersenne prime was discovered after the 30th and the 31st. Similarly, M43,112,609 was followed by two smaller Mersenne primes, first 2 weeks later and then 8 months later. ^ *** M42,643,801 was first found by a machine on April 12, 2009; however, no human took notice of this fact until June 4. Thus, either April 12 or June 4 may be considered the 'discovery' date. The discoverer, Strindmo, apparently used the alias Stig M. Valstad. To help visualize the size of the 48th known Mersenne prime, it would require 4,647 pages to display the number in base 10 with 75 digits per line and 50 lines per page. The largest known Mersenne prime (257,885,161 − 1) is also the largest known prime number.[2] M43,112,609 was the first discovered prime number with more than 10 million base-10 digits. In modern times, the largest known prime has almost always been a Mersenne prime.[69] ## Factorization of composite Mersenne numbers The factorization of a prime number is by definition the number itself. This section is about composite numbers. Mersenne numbers are very good test cases for the special number field sieve algorithm, so often the largest number factorized with this algorithm has been a Mersenne number. As of August 2012, 21,061 − 1 is the record-holder,[70] using the special number field sieve. See integer factorization records for links to more information. The special number field sieve can factorize numbers with more than one large factor. If a number has only one very large factor then other algorithms can factorize larger numbers by first finding small factors and then making a primality test on the cofactor. As of December 2011, the composite Mersenne number with largest proven prime factors is 241,521 − 1 = 41,602,235,382,028,197,528,613,357,724,450,752,065,089 × p, where p has 12,459 digits and was proven prime with ECPP.[71] The largest factorization with probable prime factors allowed is 21,168,183 − 1 = 54,763,676,838,381,762,583 × q, where q is a 351,639-digit probable prime.[72] ## Generalization The binary representation of 2p − 1 is the digit 1 repeated p times, for example, 25 − 1 = 111112 in the binary notation. A Mersenne number is therefore a repunit in base 2, and Mersenne primes are the base 2 repunit primes. The base 2 representation of a Mersenne number shows the factorization pattern for composite exponent. For example: $M_{35}=2^{35}-1=(11111111111111111111111111111111111)_2\,$ $=(11111)_2 \cdot (1000010000100001000010000100001)_2=M_5 \cdot (1000010000100001000010000100001)_2\,$ $=(1111111)_2 \cdot (10000001000000100000010000001)_2=M_7 \cdot (10000001000000100000010000001)_2\,$ $=(11111)_2 \cdot (1111111)_2 \cdot [(1000010100101010010100001)_2 - (0100001010010100101000010)_2]\,$ $=M_5 \cdot M_7 \cdot (100001010010101101011111)_2.\,$ ## Mersenne numbers in nature and elsewhere In computer science, unsigned n-bit integers can be used to express numbers up to Mn. Signed (n + 1)-bit integers can express values between −(Mn + 1) and Mn, using the two's complement representation. In the mathematical problem Tower of Hanoi, solving a puzzle with an n-disc tower requires Mn steps, assuming no mistakes are made.[73] The asteroid with minor planet number 8191 is named 8191 Mersenne after Marin Mersenne, because 8191 is a Mersenne prime (3 Juno, 7 Iris, 31 Euphrosyne and 127 Johanna having been discovered and named during the 19th century).[74] ## See also ## References 1. ^ Regius, Hudalricus. Utrisque Arithmetices Epitome. 2. ^ a b c 3. ^ Aron, Jacob (February 5, 2013). "New 17-million-digit monster is largest known prime". New Scientist. Retrieved 5 February 2013. 4. ^ "Number of primes <= 25964951". Wolfram Alpha. Retrieved 2013-03-27. 5. ^ Chris K. Caldwell, Mersenne Primes: History, Theorems and Lists 6. ^ The Prime Pages, Mersenne's conjecture. 7. ^ Bell, E.T. and Mathematical Association of America (1951). Mathematics, queen and servant of science. McGraw-Hill New York. p. 228. 8. ^ Brian Napper, The Mathematics Department and the Mark 1. 9. ^ The Prime Pages, The Prime Glossary: megaprime. 10. ^ "UCLA mathematicians discover a 13-million-digit prime number". Los Angeles Times. 2008-09-27. Retrieved 2011-05-21. 11. ^ Tia Ghose. "Largest Prime Number Discovered". Scientific American. Retrieved 2013-02-07. 12. ^ Will Edgington's Mersenne Page 13. ^ Proof of a result of Euler and Lagrange on Mersenne Divisors 14. ^ a b There is no mentioning among the ancient Egyptians of prime numbers, and they did not have any concept for prime numbers known today. In the Rhind papyrus (1650 BC) the Egyptian fraction expansions have fairly different forms for primes and composites, so it may be argued that they knew about prime numbers. See Prime Numbers Divide [Retrieved 2012-11-11]. "The Egyptians used ($) in the table above for the first primes r=3, 5, 7, or 11 (also for r=23). Here is another intriguing observation: That the Egyptians stopped the use of ($) at 11 suggests they understood (at least some parts of) Eratosthenes's Sieve 2000 years before Eratosthenes 'discovered' it." The Rhind 2/n Table [Retrieved 2012-11-11]. In the school of Pythagoras (b. about 570 – d. about 495 BC) and the Pythagoreans, we find the first sure observations of prime numbers. Hence the first two Mersenne primes, 3 and 7, were known to and may even be said to have been discovered by them. There is no reference, though, to their special form 22-1 and 23-1 as such. The sources to the knowledge of prime numbers among the Pythagoreans are late. The Neoplatonic philosopher Iamblichus, AD c. 245–c. 325, states that the Greek Platonic philosopher Speusippus, c. 408 – 339/8 BC, wrote a book named On Pythagorean Numbers. According to Iamblichus this book was based on the works of the Pythagorean Philolaus, c. 470–c. 385 BC, who lived a century after Pythagoras, 570 – c. 495 BC. In his Theology of Arithmetic in the chapter On the Decad, Iamblichus writes: "Speusippus, the son of Plato's sister Potone, and head of the Academy before Xenocrates, compiled a polished little book from the Pythagorean writings which were particularly valued at any time, and especially from the writings of Philolaus; he entitled the book On Pythagorean Numbers. In the first half of the book, he elegantly expounds linear numbers [i.e. prime numbers], polygonal numbers and all sorts of plane numbers, solid numbers and the five figures which are assigned to the elements of the universe, discussing both their individual attributes and their shared features, and their proportionality and reciprocity." Iamblichus The Theology of Arithmetic translated by Robin Waterfiled, 1988, p. 112f. [Retrieved 2012-11-11]. Iamblichus also gives us a direct quote from Speusippus' book where Speusippus among other things writes: "Secondly, it is necessary for a perfect number [the concept "perfect number" is not used here in a modern sence] to contain an equal amount of prime and incomposite numbers, and secondary and composite numbers." Iamblichus The Theology of Arithmetic translated by Robin Waterfiled, 1988, p. 113. [Retrieved 2012-11-11]. For the Greek original text, see Speusippus of Athens: A Critical Study with a Collection of the Related Texts and Commentary by Leonardo Tarán, 1981, p. 140 line 21–22 [Retrieved 2012-11-11] In his comments to Nicomachus of Gerasas's Introduction to Arithmetic, Iamblichus also mentions that Thymaridas, ca. 400 BC – ca. 350 BC, uses the term rectilinear for prime numbers, and that Theon of Smyrna, fl. AD 100, uses euthymetric and linear as alternative terms. Nicomachus of Gerasa, Introduction to Aritmetic, 1926, p. 127 [Retrieved 2012-11-11] It is unclear though when this said Thymaridas lived. "In a highly suspect passage in Iamblichus, Thymaridas is listed as a pupil of Pythagoras himself." Pythagoreanism [Retrieved 2012-11-11] Before Philolaus, c. 470–c. 385 BC, we don't have any proof of any knowledge of prime numbers. 15. ^ a b Euclid's Elements, Book IX, Proposition 36 16. ^ The Prime Pages, Mersenne Primes: History, Theorems and Lists. 17. ^ We find the oldest (undisputed) note of the result in Codex nr. 14908, which origins from Bibliotheca monasterii ord. S. Benedicti ad S. Emmeramum Ratisbonensis now in the archive of the Bayerische Staatsbibliothek, see "Halm, Karl / Laubmann, Georg von / Meyer, Wilhelm: Catalogus codicum latinorum Bibliothecae Regiae Monacensis, Bd.: 2,2, Monachii, 1876, p. 250". [retrieved on 2012-09-17] The Codex nr. 14908 consists of 10 different medieval works on mathematics and related subjects. The authors of most of these writings are known. Some authors consider the monk Fridericus Gerhart (Amman), c. 1400-d. 1465 (Frater Fridericus Gerhart monachus ordinis sancti Benedicti astrologus professus in monasterio sancti Emmerani diocesis Ratisponensis et in ciuitate eiusdem) to be the author of the part where the prime number 8191 is mentioned. Geschichte Der Mathematik [retrieved on 2012-09-17] The second manuscript of Codex nr. 14908 has the name "Regulae et exempla arithmetica, algebraica, geometrica" and the 5th perfect number and all is factors, including 8191, are mentioned on folio no. 34 a tergo (backside of p. 34). Parts of the manuscript have been published in Archiv der Mathematik und Physik, 13 (1895), pp. 388–406 [retrieved on 2012-09-23] 18. ^ "A i lettori. Nel trattato de' numeri perfetti, che giàfino dell anno 1588 composi, oltrache se era passato auáti à trouarne molti auertite molte cose, se era anco amplamente dilatatala Tauola de' numeri composti , di ciascuno de' quali si vedeano per ordine li componenti, onde preposto unnum." p. 1 in Trattato de' nvumeri perfetti Di Pietro Antonio Cataldo 1603. http://fermi.imss.fi.it/rd/bdv?/bdviewer@selid=1373775# 19. ^ p. 13–18 in Trattato de' nvumeri perfetti Di Pietro Antonio Cataldo 1603. http://fermi.imss.fi.it/rd/bdv?/bdviewer@selid=1373775# 20. ^ p. 18–22 in Trattato de' nvumeri perfetti Di Pietro Antonio Cataldo 1603. http://fermi.imss.fi.it/rd/bdv?/bdviewer@selid=1373775# 21. ^ http://bibliothek.bbaw.de/bbaw/bibliothek-digital/digitalequellen/schriften/anzeige/index_html?band=03-nouv/1772&seite:int=36 Nouveaux Mémoires de l'Académie Royale des Sciences et Belles-Lettres 1772, pp. 35–36 EULER, Leonhard: Extrait d'une lettre à M. Bernoulli, concernant le Mémoire imprimé parmi ceux de 1771. p. 318 [intitulé: Recherches sur les diviseurs de quelques nombres très grands compris dans la somme de la progression géométrique 1+101+102+103+...10T=S]. Retrieved 2011-10-02. 22. ^ http://primes.utm.edu/notes/by_year.html#31 The date and year of discovery is unsure. Dates between 1752 and 1772 are possible. 23. ^ Chris K. Caldwell. "Modular restrictions on Mersenne divisors". Primes.utm.edu. Retrieved 2011-05-21. 24. ^ “En novembre de l’année 1883, dans la correspondance de notre Académie se trouve une communication qui contient l’assertion que le nombre 261 – 1 = 2305843009213693951 est un nombre premier. /…/ Le tome XLVIII des Mémoires Russes de l’Académie /…/ contient le compte-rendu de la séance du 20 décembre 1883, dans lequel l’objet de la communication du père Pervouchine est indiqué avec précision.” Bulletin de l'Académie Impériale des Sciences de St.-Pétersbourg, s. 3, v. 31, 1887, cols. 532–533. http://www.biodiversitylibrary.org/item/107789#page/277/mode/1up [retrieved 2012-09-17] See also Mélanges mathématiques et astronomiques tirés du Bulletin de l’Académie impériale des sciences de St.-Pétersbourg v. 6 (1881–1888), p. 553–554. See also Mémoires de l'Académie impériale des sciences de St.-Pétersbourg: Sciences mathématiques, physiques et naturelles, vol. 48 25. ^ http://www.jstor.org/stable/2972574 The American Mathematical Monthly, Vol. 18, No. 11 (Nov., 1911), pp. 195-197. The article is signed "DENVER, COLORADO, June, 1911". Retrieved 2011-10-02. 26. ^ "M. E. Fauquenbergue a trouvé ses résultats depuis Février, et j’en ai reçu communication le 7 Juin; M. Powers a envoyé le 1er Juin un cablógramme à M. Bromwich [secretary of London Mathematical Society] pour M107. Sur ma demande, ces deux auteurs m’ont adressé leurs remarquables résultats, et je m’empresse de les publier dans nos colonnes, avec nos felicitations." p. 103, André Gérardin, Nombres de Mersenne pp. 85, 103–108 in Sphinx-Œdipe. [Journal mensuel de la curiosité, de concours & de mathématiques.] v. 9, No. 1, 1914. 27. ^ "Power's cable announcing this same result was sent to the London Math. So. on 1 June 1914." Mersenne's Numbers, Scripta Mathematica, v. 3, 1935, p. 112–119 http://primes.utm.edu/mersenne/LukeMirror/lit/lit_008s.htm [retrieved 2012-10-13] 28. ^ http://plms.oxfordjournals.org/content/s2-13/1/1.1.full.pdf Proceedings / London Mathematical Society (1914) s2-13 (1): 1. Result presented at a meeting with London Mathematical Society on June 11, 1914. Retrieved 2011-10-02. 29. ^ The Prime Pages, M107: Fauquembergue or Powers?. 30. ^ http://visualiseur.bnf.fr/CadresFenetre?O=NUMM-3039&I=166&M=chemindefer Presented at a meeting with Académie des sciences (France) on January 10, 1876. Retrieved 2011-10-02. 31. ^ a b "Using the standard Lucas test for Mersenne primes as programmed by R. M. Robinson, the SWAC has discovered the primes 2521 - 1 and 2607 - 1 on January 30, 1952." D. H. Lehmer, Recent Discoveries of Large Primes, Mathematics of Computation, vol. 6, No. 37 (1952), p. 61, http://www.ams.org/journals/mcom/1952-06-037/S0025-5718-52-99404-0/S0025-5718-52-99404-0.pdf [Retrieved 2012-09-18] 32. ^ "The program described in Note 131 (c) has produced the 15th Mersenne prime 21279 - 1 on June 25. The SWAC tests this number in 13 minutes and 25 seconds." D. H. Lehmer, A New Mersenne Prime, Mathematics of Computation, vol. 6, No. 39 (1952), p. 205, http://www.ams.org/journals/mcom/1952-06-039/S0025-5718-52-99387-3/S0025-5718-52-99387-3.pdf [Retrieved 2012-09-18] 33. ^ a b "Two more Mersenne primes, 22203 - 1 and 22281 - 1, were discovered by the SWAC on October 7 and 9, 1952." D. H. Lehmer, Two New Mersenne Primes, Mathematics of Computation, vol. 7, No. 41 (1952), p. 72, http://www.ams.org/journals/mcom/1953-07-041/S0025-5718-53-99371-5/S0025-5718-53-99371-5.pdf [Retrieved 2012-09-18] 34. ^ "On September 8, 1957, the Swedish electronic computer BESK established that the Mersenne number M3217 = 23217 - 1 is a prime." Hans Riesel, A New Mersenne Prime, Mathematics of Computation, vol. 12 (1958), p. 60, http://www.ams.org/journals/mcom/1958-12-061/S0025-5718-1958-0099752-6/S0025-5718-1958-0099752-6.pdf [Retrieved 2012-09-18] 35. ^ a b A. Hurwitz and J. L. Selfridge, Fermat numbers and perfect numbers, Notices of the American Mathematical Society, v. 8, 1961, p. 601, abstract 587-104. 36. ^ a b "If p is prime, Mp = 2p - 1 is called a Mersenne number. The primes M4253 and M4423 were discovered by coding the Lucas-Lehmer test for the IBM 7090." Alexander Hurwitz, New Mersenne Primes, Mathematics of Computation, vol. 16, No. 78 (1962), p. 249–251, http://www.ams.org/journals/mcom/1962-16-078/S0025-5718-1962-0146162-X/S0025-5718-1962-0146162-X.pdf [Retrieved 2012-09-18] 37. ^ a b c "The primes M9689, M9941, and M11213 which are now the largest known primes, were discovered by Illiac II at the Digital Computer Laboratory of the University of Illinois." Donald B. Gillies, Three New Mersenne Primes and a Statistical Theory, Mathematics of Computation, vol. 18, No. 85 (1964), p. 93–97, http://www.ams.org/journals/mcom/1964-18-085/S0025-5718-1964-0159774-6/S0025-5718-1964-0159774-6.pdf [Retrieved 2012-09-18] 38. ^ "On the evening of March 4, 1971, a zero Lucas-Lehmer residue for p = p24 = 19937 was found. Hence, M19937 is the 24th Mersenne prime." Bryant Tuckerman, The 24th Mersenne Prime, Proceedings of the National Academy of Sciences of the United States of America, vol. 68:10 (1971), p. 2319–2320, http://www.pnas.org/content/68/10/2319.full.pdf [Retrieved 2012-09-18] 39. ^ "On October 30, 1978 at 9:40 pm, we found M21701 to be prime. The CPU time required for this test was 7:40:20. Tuckerman and Lehmer later provided confirmation of this result." Curt Noll and Laura Nickel, The 25th and 26th Mersenne Primes, Mathematics of Computation, vol. 35, No. 152 (1980), p. 1387–1390, http://www.ams.org/journals/mcom/1980-35-152/S0025-5718-1980-0583517-4/S0025-5718-1980-0583517-4.pdf [Retrieved 2012-09-18] 40. ^ "Of the 125 remaining Mp only M23209 was found to be prime. The test was completed on February 9, 1979 at 4:06 after 8:39:37 of CPU time. Lehmer and McGrogan later confirmed the result." Curt Noll and Laura Nickel, The 25th and 26th Mersenne Primes, Mathematics of Computation, vol. 35, No. 152 (1980), p. 1387–1390, http://www.ams.org/journals/mcom/1980-35-152/S0025-5718-1980-0583517-4/S0025-5718-1980-0583517-4.pdf [Retrieved 2012-09-18] 41. ^ David Slowinski, "Searching for the 27th Mersenne Prime", Journal of Recreational Mathematics, v. 11(4), 1978–79, p. 258–261, MR 80g #10013 42. ^ "The 27th Mersenne prime. It has 13395 digits and equals 244497-1. [...] Its primeness was determined on April 8, 1979 using the Lucas-Lehmer test. The test was programmed on a CRAY-1 computer by David Slowinski & Harry Nelson." (p. 15) "The result was that after applying the Lucas-Lehmer test to about a thousand numbers, the code determined, on Sunday, April 8th, that 244497 - 1 is, in fact, the 27th Mersenne prime." (p. 17), David Slowinski, "Searching for the 27th Mersenne Prime", Cray Channels, vol. 4, no. 1, (1982), pp. 15–17. 43. ^ "An FFT containing 8192 complex elements, which was the minimum size required to test M110503, ran aproximately 11 minutes on the SX-2. The discovery of M110503 (January 29, 1988) has been confirmed." W. N. Colquitt and L. Welsh, Jr., A New Mersenne Prime, Mathematics of Computation, vol. 56, No. 194 (April 1991), p. 867–870, http://www.ams.org/journals/mcom/1991-56-194/S0025-5718-1991-1068823-9/S0025-5718-1991-1068823-9.pdf [Retrieved 2012-09-18] 44. ^ "This week, two computer experts found the 31st Mersenne prime. But to their surprise, the newly discovered prime number falls between two previously known Mersenne primes. It occurs when p = 110,503, making it the third-largest Mersenne prime known." I. Peterson, Priming for a lucky strike Science News; 2/6/88, Vol. 133 Issue 6, p. 85-85. http://ehis.ebscohost.com/ehost/detail?vid=3&hid=23&sid=9a9d7493-ffed-410b-9b59-b86c63a93bc4%40sessionmgr10&bdata=JnNpdGU9ZWhvc3QtbGl2ZQ%3d%3d#db=afh&AN=8824187 [Retrieved 2012-09-18] 45. ^ "Mersenne Prime Numbers". Omes.uni-bielefeld.de. 2011-01-05. Retrieved 2011-05-21. 46. ^ "Slowinski, a software engineer for Cray Research Inc. in Chippewa Falls, discovered the number at 11:36 a.m. Monday. [i.e. 1983 September 19]" Jim Higgins, "Elusive numeral's number is up" and "Scientist finds big number" in The Milwaukee Sentinel – Sep 24, 1983, p. 1, p. 11 [retrieved 2012-10-23] 47. ^ "The number is the 30th known example of a Mersenne prime, a number divisible only by 1 and itself and written in the form 2p-1, where the exponent p is also a prime number. For instance, 127 is a Mersenne number for which the exponent is 7. The record prime number's exponent is 216,091." I. Peterson, Prime time for supercomputers Science News; 9/28/85, Vol. 128 Issue 13, p. 199. http://ehis.ebscohost.com/ehost/detail?vid=4&hid=22&sid=c11090a2-4670-469f-8f75-947b593a56a0%40sessionmgr10&bdata=JnNpdGU9ZWhvc3QtbGl2ZQ%3d%3d#db=afh&AN=8840537 [Retrieved 2012-09-18] 48. ^ "Slowinski's program also found the 28th in 1982, the 29th in 1983, and the 30th [known at that time] this past Labor Day weekend. [i.e. August 31-September 1, 1985]" Rad Sallee, "`Supercomputer'/Chevron calculating device finds a bigger prime number" Houston Chronicle, Friday 09/20/1985, Section 1, Page 26, 4 Star Edition [retrieved 2012-10-23] 49. ^ The Prime Pages, The finding of the 32nd Mersenne. 50. ^ Chris Caldwell, The Largest Known Primes. 51. ^ Crays press release 52. ^ Slowinskis email 53. ^ Silicon Graphics' press release http://web.archive.org/web/19970606011821/http://www.sgi.com/Headlines/1996/September/prime.html [Retrieved 2012-09-20] 54. ^ The Prime Pages, A Prime of Record Size! 21257787-1. 55. ^ 56. ^ 57. ^ 58. ^ 59. ^ 60. ^ 61. ^ 62. ^ 63. ^ 64. ^ 65. ^ a b Titanic Primes Raced to Win$100,000 Research Award. Retrieved on 2008-09-16.
66. ^ "On April 12th [2009], the 47th known Mersenne prime, 242,643,801-1, a 12,837,064 digit number was found by Odd Magnar Strindmo from Melhus, Norway! This prime is the second largest known prime number, a "mere" 141,125 digits smaller than the Mersenne prime found last August.", The List of Largest Known Primes Home Page, http://primes.utm.edu/primes/page.php?id=88847 [retrieved 2012-09-18]
67. ^ Woltman, George. "NEW MERSENNE PRIME! TOTALLY MERSENNE THIS TIME! thread". mersenneforum. Retrieved 5 February 2013.
68. ^ a b GIMPS Milestones Report. Retrieved 2013-02-14
69. ^ The largest known prime has been a Mersenne prime since 1952, except between 1989 and 1992; see Caldwell, "The Largest Known Prime by Year: A Brief History" from the Prime Pages website, University of Tennessee at Martin.
70. ^
71. ^ Chris Caldwell, The Top Twenty: Mersenne cofactor at The Prime Pages. Retrieved 2012-12-08.
72. ^ Henri Lifchitz and Renaud Lifchitz. "PRP Top Records". Retrieved 2011-12-21.
73. ^ Petković, Miodrag (2009). Famous Puzzles of Great Mathematicians. AMS Bookstore. p. 197. ISBN 0-8218-4814-3.
74. ^ Alan Chamberlin. "JPL Small-Body Database Browser". Ssd.jpl.nasa.gov. Retrieved 2011-05-21.