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%I #11 Mar 19 2017 15:59:54
%S 1,1,2,6,24,48,182,868,5752,37156,296944,2738820,28894206,335399468,
%T 4285522402,59536763892,892785282788
%N Number of permutations p of 1,2,...,n satisfying |p(i+1)-p(i)|<>4 and |p(j+4)-p(j)|<>1 for all i=1..n-1, j=1..n-4.
%C a(n) is also the number of ways to place n nonattacking pieces rook + leaper[1,4] on an n X n chessboard (in fairy chess the leaper[1,4] is called a giraffe).
%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)
%F Asymptotic: a(n)/n! ~ 1/e^4.
%Y Cf. A137774, A189358.
%K nonn,more,hard
%O 0,3
%A _Vaclav Kotesovec_, Apr 23 2011
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