205 (number)

Last updated
204 205 206
Cardinal two hundred five
Ordinal 205th
(two hundred fifth)
Factorization 5 × 41
Divisors 1, 5, 41, 205
Greek numeral ΣΕ´
Roman numeral CCV
Binary 110011012
Ternary 211213
Senary 5416
Octal 3158
Duodecimal 15112
Hexadecimal CD16

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

Contents

In mathematics

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 or less. [3] There are 205 different ways of forming a connected graph by adding six edges to a set of five labeled vertices. [4]

In other fields

See also

Related Research Articles

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References

  1. Sloane, N. J. A. (ed.). "SequenceA000959(Lucky numbers)". The On-Line Encyclopedia of Integer Sequences . OEIS Foundation.
  2. Sloane, N. J. A. (ed.). "SequenceA007406(Wolstenholme numbers)". The On-Line Encyclopedia of Integer Sequences . OEIS Foundation.
  3. Sloane, N. J. A. (ed.). "SequenceA018836(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.). "SequenceA061540(Number of connected labeled graphs with n nodes and n+1 edges)". The On-Line Encyclopedia of Integer Sequences . OEIS Foundation.