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%I #9 Apr 14 2021 22:27:42
%S 1,3,24,4995,10763361,211822552035,37523658921114744,
%T 59824832307866205347043,858420955073128584419531008641,
%U 110856622060759442496180656754310346403,128844380183002832759115461915902241562318377784,1347757724935823407809884872163997148505019182125807296675
%N Number of ways to label points of an n X n grid with 3 colors, up to rotational symmetry.
%C Labels of adjacent points need not be distinct.
%H Andrew Howroyd, <a href="/A047938/b047938.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 = 3.
%Y Column k=3 of A343095.
%Y See A068253 for number of proper colorings.
%Y Cf. A054739, A047937, A047939.
%K nonn
%O 0,2
%A _Rob Pratt_
%E Terms a(10) and beyond from _Andrew Howroyd_, Apr 14 2021