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%I #6 Sep 12 2015 11:00:25
%S 1,2,6,24,120,720,3312,18688,127104,990208,8878016,89267712,789509184,
%T 7803741824,85447337472,1008717911040
%N Number of ways to place n nonattacking composite pieces rook + rider[3,6] on an n X n chessboard.
%C a(n) is also number of permutations p of 1,2,...,n satisfying |p(i+3k)-p(i)|<>6k AND |p(j+6k)-p(j)|<>3k for all i>=1, j>=1, k>=1, i+3k<=n, j+6k<=n
%H V. Kotesovec, <a href="https://oeis.org/wiki/User:Vaclav_Kotesovec">Number of ways of placing non-attacking queens, kings, bishops and knights</a> (in English and Czech)
%H Wikipedia, <a href="http://en.wikipedia.org/wiki/Fairy_chess_piece">Fairy chess piece</a>
%Y Cf. A000170, A189853, A189857
%K nonn,hard
%O 1,2
%A _Vaclav Kotesovec_, Apr 29 2011
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