A220865 Number of perfect matchings in the graph Petersen X P_n.

6, 472, 14508, 616945, 23310528, 919890493, 35726458296, 1395733639864, 54409227545670, 2122708670082349, 82790398883086464, 3229363021350300853, 125961061338940140882, 4913174522492216122360, 191639794681507592618832, 7474980745741030831444357, 291564159140628690376670784, 11372562031468273218156678121, 443590715863319911428764167260, 17302409958226333533759796319896

Offset

1,1

Links

Andrew Howroyd, Table of n, a(n) for n = 1..30

S. Butler and S. Osborne, Counting tilings by taking walks, 2012.

Crossrefs

Sequence in context: A332146 A132590 A112945 * A080295 A084108 A269761

Adjacent sequences: A220862 A220863 A220864 * A220866 A220867 A220868

Keyword

nonn

Author

N. J. A. Sloane, Dec 27 2012

Extensions

a(8)-a(20) from Andrew Howroyd, Nov 15 2015

Status

approved