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%I #15 Sep 23 2019 06:27:23
%S 1,186,923526,122408393436,433110977725751106,
%T 40908457493732914322944536,103146129375410533061371714364918916,
%U 6942544711174164051575906086886643368922134556,12474132532762777585883439690925675118905860580968258566406
%N 1/7 the number of colorings of an n X n square array with 7 colors.
%H Jean-François Alcover, <a href="/A068257/b068257.txt">Table of n, a(n) for n = 1..13</a>
%t A222340 = Cases[Import["https://oeis.org/A222340/b222340.txt", "Table"], {_, _}][[All, 2]];
%t a[n_] := A222340[[2 n^2 - 2 n + 1]];
%t Table[a[n], {n, 1, 13}] (* _Jean-François Alcover_, Sep 23 2019 *)
%Y Main diagonal of A222340.
%Y Cf. A068239-A068305, A000332, A002417, A027441, A182368, A182406.
%K nonn
%O 1,2
%A _R. H. Hardin_, Feb 24 2002
%E a(7)-a(9) from _Alois P. Heinz_, Apr 27 2012