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%I #27 Nov 08 2022 02:18:05
%S 1,1,2,6,24,120,696,4572,34260,290328,2751480,28686024,328764732,
%T 4106158164,55495145304,806797105320,12554890849992,208164423163908,
%U 3663256621120548,68188490015132040,1338490745511631080,27630826605742438968
%N Number of permutations p of 1,2,...,n satisfying p(i+5)-p(i)<>5 for all 1<=i<=n-5.
%C a(n) is also number of ways to place n nonattacking pieces rook + semi-leaper[5,5] on an n X n chessboard.
%H Vaclav Kotesovec, <a href="/A189284/b189284.txt">Table of n, a(n) for n = 0..26</a> (Updated Jan 19 2019)
%H Vaclav Kotesovec, <a href="https://oeis.org/wiki/User:Vaclav_Kotesovec">Non-attacking chess pieces</a>, 6ed, 2013, p. 644.
%H Vaclav Kotesovec, <a href="/A189284/a189284.txt">Mathematica program for this sequence</a>
%H George Spahn and Doron Zeilberger, <a href="https://arxiv.org/abs/2211.02550">Counting Permutations Where The Difference Between Entries Located r Places Apart Can never be s (For any given positive integers r and s)</a>, arXiv:2211.02550 [math.CO], 2022.
%F Asymptotics (V. Kotesovec, Mar 2011): a(n)/n! ~ (1 + 9/n + 20/n^2)/e.
%Y Cf. A000255, A189281, A189282, A189283, A189256.
%K nonn,hard
%O 0,3
%A _Vaclav Kotesovec_, Apr 19 2011
%E Terms a(25)-a(26) from _Vaclav Kotesovec_, Apr 20 2012
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