A047942 - OEIS

%I #9 Apr 14 2021 22:28:12

%S 1,7,616,10092775,8308234084801,335267154940213889575,

%T 662932711464913775048175499816,

%U 64230894380264719522488136461023341060807,304940121908958925034643465916849873749900601574419201,70938377295002676956115265690779190293441720530070400876280330568007

%N Number of 7-colorings of an n X n grid, up to rotational symmetry.

%H Andrew Howroyd, <a href="/A047942/b047942.txt">Table of n, a(n) for n = 0..25</a>

%F a(n) = (m^(n^2) + 2 m^((n^2 + 3 (n mod 2))/4) + m^((n^2 + (n mod 2))/2))/4, with m = 7.

%Y Column k=7 of A343095.

%Y Cf. A047937.

%K nonn

%O 0,2

%A _Rob Pratt_

%E Terms a(8) and beyond from _Andrew Howroyd_, Apr 14 2021