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A143248 Number of (directed) Hamiltonian circuits in the complete bipartite graph K_{n,n}. 0
0, 12, 144, 2880, 86400, 3628800, 203212800, 14631321600, 1316818944000, 144850083840000, 19120211066880000, 2982752926433280000, 542861032610856960000, 114000816848279961600000 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..14.

Eric Weisstein's World of Mathematics, BipartiteGraph

Eric Weisstein's World of Mathematics, HamiltonianCycle

FORMULA

a(1) = 0, a(n) = n!(n+1)!

a(n)=A010790(n), n>1. [From R. J. Mathar, Aug 15 2008]

CROSSREFS

Sequence in context: A000468 A076728 A123237 * A138444 A137886 A097303

Adjacent sequences:  A143245 A143246 A143247 * A143249 A143250 A143251

KEYWORD

nonn

AUTHOR

Eric W. Weisstein, Aug 01, 2008

STATUS

approved

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Last modified November 23 04:44 EST 2014. Contains 249839 sequences.