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%I #7 Oct 21 2014 03:41:24
%S 1,2,15,207,6084,292607,23511001,3132847224,693856861039,
%T 259806377729539
%N Number of ways of placing kings with no more than 3 mutual attacks on an n X n chessboard.
%Y Cf. A143870, A143875, A143886.
%Y Cf. A143882, A143883, A143884, A143885.
%K nonn,more,hard
%O 0,2
%A _R. H. Hardin_, Sep 04 2008