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%I #6 Sep 12 2015 11:00:25
%S 1,2,6,24,120,672,4128,28992,231936,2088960,20017152,207208704,
%T 2326900992,28338241536,373152276480,5206300028928
%N Number of ways to place n nonattacking composite pieces rook + rider[5,5] on an n X n chessboard.
%C a(n) is also number of permutations p of 1,2,...,n satisfying |p(j+5k)-p(j)|<>5k for all j>=1, k>=1, j+5k<=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. A189256, A000170, A189838, A189839, A189840
%K nonn,hard
%O 1,2
%A _Vaclav Kotesovec_, Apr 29 2011
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