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A068256
1/6 the number of colorings of an n X n square array with 6 colors.
3
1, 105, 194485, 6354787485, 3662978221194885, 37246546285522069805565, 6681224184095576349599961437005, 21141920893108925844961568245788270386085, 1180188030501408210062775052100916976604905321333565, 1162187850685436026547128866816039344195930156602955871508107885
OFFSET
1,2
LINKS
Jean-François Alcover, Table of n, a(n) for n = 1..13
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 *)
CROSSREFS
Main diagonal of A222281.
Sequence in context: A199100 A225217 A096150 * A062031 A199522 A036201
KEYWORD
nonn
AUTHOR
R. H. Hardin, Feb 24 2002
EXTENSIONS
a(8)-a(10) from Alois P. Heinz, Apr 27 2012
STATUS
approved