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%I #9 Mar 19 2017 16:22:35
%S 1,1,2,6,24,120,392,1810,10400,72228,589674,5196870,52398658,
%T 588036216,7274466172,98024173852,1427556373892
%N Number of permutations p of 1,2,...,n satisfying |p(i+2)-p(i)|<>5 and |p(j+5)-p(j)|<>2 for all i=1..n-2, j=1..n-5.
%C a(n) is also the number of ways to place n nonattacking pieces rook + leaper[2,5] on an n X n chessboard.
%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, A189563, A189564, A189565, A189566.
%K nonn,more,hard
%O 0,3
%A _Vaclav Kotesovec_, Apr 23 2011
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