A068256 1/6 the number of colorings of an n X n square array with 6 colors.

1, 105, 194485, 6354787485, 3662978221194885, 37246546285522069805565, 6681224184095576349599961437005, 21141920893108925844961568245788270386085, 1180188030501408210062775052100916976604905321333565, 1162187850685436026547128866816039344195930156602955871508107885

Offset: 1

Author

R. H. Hardin, Feb 24 2002

Keywords

• nonn

Links

• Jean-François Alcover, Table of n, a(n) for n = 1..13

Crossrefs

Main diagonal of A222281.

Cf. A068239-A068305, A000332, A002417, A027441, A182368, A182406.

Programs

Mathematica

A222281 = Cases[Import["https://oeis.org/A222281/b222281.txt", "Table"], {, }][[All, 2]];
a[n_] := A222281[[2 n^2 - 2 n + 1]];
Table[a[n], {n, 1, 13}] (* Jean-François Alcover, Sep 23 2019 *)

Extensions

a(8)-a(10) from Alois P. Heinz, Apr 27 2012