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%I #10 Feb 24 2019 15:30:36
%S 1,1,2,6,14,53,265,1554,11024,90816,846032,8803826,101011765,
%T 1265197857,17167351014,250725968406,3920074915626,65310957981693,
%U 1154885557082749,21599009876309400,425919898969718528,8831294211199266816,192065262001816123136
%N Number of permutations p of [n] having no index i with |p(i)-i| = 3.
%H Alois P. Heinz, <a href="/A324365/b324365.txt">Table of n, a(n) for n = 0..250</a>
%H Wikipedia, <a href="https://en.wikipedia.org/wiki/Permutation">Permutation</a>
%F a(n) = n! - A324366(n).
%e a(4) = 14: 1234, 1243, 1324, 1342, 1423, 1432, 2134, 2143, 2314, 2413, 3124, 3142, 3214, 3412.
%Y Column k=3 of A306512.
%Y Cf. A000142, A324366.
%K nonn
%O 0,3
%A _Alois P. Heinz_, Feb 23 2019
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