|
%I #6 Sep 12 2015 11:00:25
%S 1,0,0,2,10,4,12,32,96,144,528,1712,7472,24500,103536,486020,2218808,
%T 11113020,59242576,342584556,1981826412
%N Number of ways to place n nonattacking composite pieces queen + rider[4,5] on an n X n chessboard.
%C a(n) is also number of permutations p of 1,2,...,n satisfying |p(i+4k)-p(i)|<>5k AND |p(j+5k)-p(j)|<>4k AND |p(m+k)-p(m)|<>k for all i>=1, j>=1, m>=1, k>=1, i+4k<=n, j+5k<=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, A189875, A189878, A189880, A189861
%K nonn,hard
%O 1,4
%A _Vaclav Kotesovec_, Apr 29 2011
|
