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%I #68 Dec 24 2018 08:56:12
%S 1,14,459,35312,4072108,638653285,128441726634,31872148398195,
%T 9490641145219266,3321018871480028710
%N Number of nonequivalent ways to place n^2 nonattacking kings on a 2n X 2n chessboard under all symmetry operations of the square.
%C A maximum of n^2 nonattacking kings may be placed on a 2n X 2n chessboard.
%F a(n) = A236679(2n+1, n^2).
%e For n = 2 there are a(2) = 14 distinct solutions from 79 that will not be repeated at all possible turns and reflections.
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%e 9. 10.
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%e 11. 12.
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%e 13. 14.
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%Y Cf. A018807 (rotations and reflections considered distinct).
%Y Cf. A137432 (on cylindrical chessboard).
%Y Cf. A236679, A322284, A321614.
%K nonn,more
%O 1,2
%A _Anton Nikonov_, Dec 21 2018
%E a(4)-a(10) from _Andrew Howroyd_, Dec 21 2018