%I #4 Mar 31 2012 12:35:06
%S 1,2,4,26,35,821,1462,148176,221880,96574099,126381799,196582061878,
%T 269726664738,1805524692669120,2273457768078921,66873306557904082902,
%U 76981272132177635155,9380430300181898788236006
%N Number of ways of placing non-attacking knights on an n X n chessboard symmetric under horizontal reflection.
%K nonn
%O 0,2
%A _R. H. Hardin_, Aug 25 2008