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Table of n, a(n) for n=1..14.
Eric Weisstein's World of Mathematics, BipartiteGraph
Eric Weisstein's World of Mathematics, HamiltonianCycle
a(1) = 0, a(n) = n!(n+1)!
a(n) = A010790(n), n>1. - R. J. Mathar, Aug 15 2008
Sequence in context: A000468 A076728 A123237 * A138444 A137886 A097303
Adjacent sequences: A143245 A143246 A143247 * A143249 A143250 A143251
Eric W. Weisstein, Aug 01 2008