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A124355
Number of (directed) Hamiltonian cycles on the complete graph K_n.
1
0, 0, 2, 6, 24, 120, 720, 5040, 40320, 362880, 3628800, 39916800, 479001600, 6227020800, 87178291200, 1307674368000, 20922789888000, 355687428096000, 6402373705728000, 121645100408832000, 2432902008176640000
OFFSET
1,3
COMMENTS
a(n) is also the number of (directed) Hamiltonian paths on the complete graph K_{n-1}.
LINKS
FORMULA
a(1) = 0, a(2) = 0, a(n) = (n-1)! = A104150(n) for n > 2. - Georg Fischer, Oct 21 2018
CROSSREFS
Sequence in context: A254523 A289282 A155456 * A133942 A159333 A165233
KEYWORD
nonn
AUTHOR
Eric W. Weisstein, Nov 05 2006
STATUS
approved