A287230 Number of matchings in the n-triangular honeycomb acute knight graph.

1, 1, 8, 64, 1331, 64000, 6400075, 1404928000, 677298787768, 712186032947200, 1635557819719974912, 8209592592625295700893, 90036881979773511965369428, 2157454308508779392217680572439

Offset

1,3

Links

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

Stan Wagon, Graph Theory Problems from Hexagonal and Traditional Chess, The College Mathematics Journal, Vol. 45, No. 4, September 2014, pp. 278-287.

Eric Weisstein's World of Mathematics, Independent Edge Set

Eric Weisstein's World of Mathematics, Matching

Crossrefs

Cf. A289143, A287204, A289904, A287228, A269869.

Sequence in context: A111984 A352721 A278145 * A376446 A154710 A069033

Adjacent sequences: A287227 A287228 A287229 * A287231 A287232 A287233

Keyword

nonn,more

Author

Eric W. Weisstein, May 22 2017

Extensions

a(11) from Eric W. Weisstein, Jun 25 2017

a(12)-a(14) from Andrew Howroyd, Jul 17 2017

Status

approved