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%I #24 Nov 08 2022 02:18:08
%S 1,1,2,6,24,114,628,4062,30360,255186,2414292,25350954,292378968,
%T 3673917102,49928069188,729534877758,11403682481112,189862332575658,
%U 3354017704180052,62654508729565554,1233924707891272728,25550498290562247438
%N Number of permutations p of 1,2,...,n satisfying p(i+4)-p(i)<>4 for all 1<=i<=n-4.
%C a(n) is also number of ways to place n nonattacking pieces rook + semi-leaper[4,4] on an n X n chessboard.
%H Vaclav Kotesovec, <a href="/A189283/b189283.txt">Table of n, a(n) for n = 0..27</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="/A189283/a189283.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 + 7/n + 12/n^2)/e.
%Y Cf. A000255, A189281, A189282, A189255.
%K nonn,hard
%O 0,3
%A _Vaclav Kotesovec_, Apr 19 2011
%E Terms a(26)-a(27) from _Vaclav Kotesovec_, Apr 20 2012
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