205 (number)

← 204 205 206 →
← 200 201 202 203 204 205 206 207 208 209 → List of numbers Integers ← 0 100 200 300 400 500 600 700 800 900 →
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.

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.^[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

• The atomic number of an element temporarily called Binilpentium

See also

• List of highways numbered 205
• 205 Martha, a large Main belt asteroid
• 205 Yonge Street, a building in Toronto
• 205 series, a commuter train type in Japan
• Peugeot 205, a French car
• WWE 205 Live, an American professional wrestling program

References

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.