A180584 Number of Hamiltonian cycles in C_8 X P_n.

1, 10, 318, 6114, 126426, 2588218, 53055038, 1087362018, 22286085818, 456763781330, 9361593883038, 191870363459178, 3932475321605194, 80597971743535618, 1651894168575456078, 33856364932336405826

Offset

1,2

Links

Table of n, a(n) for n=1..16.

Artem M. Karavaev, FlowProblem.ru web-project: Hamilton Cycles page.

Formula

a(1) = 1,

a(2) = 10,

a(3) = 318,

a(4) = 6114,

a(5) = 126426,

a(6) = 2588218,

a(7) = 53055038,

a(8) = 1087362018,

a(9) = 22286085818,

a(10) = 456763781330,

a(11) = 9361593883038,

a(12) = 191870363459178,

a(13) = 3932475321605194,

a(14) = 80597971743535618,

a(15) = 1651894168575456078,

a(16) = 33856364932336405826,

a(17) = 693902471632291156946,

a(18) = 14221864665640856614738,

a(19) = 291483951760814319838934,

a(20) = 5974103686936428822276538,

a(21) = 122442126390395191122751354 and

a(n) = 40a(n-20) - 72a(n-19) - 84a(n-18) + 928a(n-17) - 1018a(n-16) +

584a(n-15) - 3848a(n-14) - 11373a(n-13) - 4467a(n-12) - 1318a(n-11) +

5873a(n-10) + 11998a(n-9) + 8806a(n-8) + 5041a(n-7) + 2919a(n-6) +

22a(n-5) - 218a(n-4) - 345a(n-3) - 34a(n-2) + 23a(n-1), n>21.

Crossrefs

Sequence in context: A291561 A302933 A372729 * A048345 A325726 A223298

Adjacent sequences: A180581 A180582 A180583 * A180585 A180586 A180587

Keyword

nonn

Author

Artem M. Karavaev, Sep 10 2010

Status

approved