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Number of ways to place n nonattacking composite pieces rook + rider[3,5] on an n X n chessboard.
2

%I #6 Sep 12 2015 11:00:25

%S 1,2,6,24,120,464,2274,13236,91760,740562,5305548,43237840,395858894,

%T 4087066620,46633569480,509698057110

%N Number of ways to place n nonattacking composite pieces rook + rider[3,5] 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)|<>5k AND |p(j+5k)-p(j)|<>3k for all i>=1, j>=1, k>=1, i+3k<=n, 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. A000170, A189852, A189856

%K nonn,hard

%O 1,2

%A _Vaclav Kotesovec_, Apr 29 2011