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Number of ways to place n nonattacking composite pieces queen + rider[1,3] on an n X n chessboard.
3

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

%S 1,0,0,0,0,0,0,0,0,4,56,18,116,112,408,916,2400,7228,27368,111478,

%T 445644,1674860,7624368,38737270,178933064

%N Number of ways to place n nonattacking composite pieces queen + rider[1,3] on an n X n chessboard.

%C In fairy chess, the rider [1,3] is called a Camelrider.

%C a(n) is also number of permutations p of 1,2,...,n satisfying |p(i+k)-p(i)|<>3k AND |p(j+3k)-p(j)|<>k AND |p(m+k)-p(m)|<>k for all i>=1, j>=1, m>=1, k>=1, i+k<=n, j+3k<=n, m+k<=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. A102388, A189850

%K nonn,hard

%O 1,10

%A _Vaclav Kotesovec_, Apr 29 2011