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%I #7 Dec 21 2016 12:18:51
%S 1,0,2,14,273,7855,311552,14895797,831959075,52959962415
%N Number of non-equivalent ways to place n non-attacking kings on an n X n board.
%C Rotations and reflections of placements are not counted. If they are to be counted, see A201513.
%e There are 14 non-equivalent ways to place 4 non-attacking kings on a 4 X 4 board, e.g., this one:
%e K..K
%e ....
%e ....
%e K..K
%Y Cf. A201513, A279111 (2 kings), A279112 (3 kings), A279113 (4 kings), A279114 (5 kings), A279115 (6 kings), A279116 (7 kings), A236679.
%K nonn,more
%O 1,3
%A _Heinrich Ludwig_, Dec 10 2016