205 (number)

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← 204 205 206 →
Cardinaltwo hundred five
Ordinal205th
(two hundred fifth)
Factorization5 × 41
Divisors1, 5, 41, 205
Greek numeralΣΕ´
Roman numeralCCV
Binary110011012
Ternary211213
Quaternary30314
Quinary13105
Senary5416
Octal3158
Duodecimal15112
HexadecimalCD16
VigesimalA520
Base 365P36

205 (two hundred [and] five) is the natural number following 204 and preceding 206.

In mathematics[edit]

205 is a lucky number,[1] and a Wolstenholme number.[2] On an infinite chessboard, a knight can reach exactly 205 squares within four moves.[3] There are 205 different ways of forming a connected graph by adding six edges to a set of five labeled vertices.[4]

See also[edit]

References[edit]

  1. ^ Sloane, N. J. A. (ed.). "Sequence A000959 (Lucky numbers)". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation.
  2. ^ Sloane, N. J. A. (ed.). "Sequence A007406 (Wolstenholme numbers)". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation.
  3. ^ Sloane, N. J. A. (ed.). "Sequence A018836 (Number of squares on infinite chess-board at <= n knight's moves from a fixed square)". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation.
  4. ^ Sloane, N. J. A. (ed.). "Sequence A061540 (Number of connected labeled graphs with n nodes and n+1 edges)". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation.