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A260111 Number of permutations p of [n] with no fixed points and cyclic displacement of elements restricted by six: p(i)<>i and (i-p(i) mod n <= 6 or p(i)-i mod n <= 6).

%I A260111 #16 Jan 06 2016 12:24:17
%S A260111 1,0,1,2,9,44,265,1854,14833,133496,1334961,14684570,176214841,
%T A260111 2290792932,10930514688,52034548064,247272708868,1173385630596,
%U A260111 5560837425792,26322368822528,124470922522980,589274182149120,2793967092494408,13269446868206480,63125696320334912
%N A260111 Number of permutations p of [n] with no fixed points and cyclic displacement of elements restricted by six: p(i)<>i and (i-p(i) mod n <= 6 or p(i)-i mod n <= 6).
%C A260111 a(n) = A000166(n) for n <= 13.
%p A260111 a:= n-> `if`(n=0, 1, LinearAlgebra[Permanent](Matrix(n, (i, j)->
%p A260111         `if`(i<>j and (i-j mod n<=6 or j-i mod n<=6), 1, 0)))):
%p A260111 seq(a(n), n=0..16);
%t A260111 a[n_] := If[n == 0, 1, Permanent[Table[If[i != j && (Mod[i - j, n] <= 6 || Mod[j - i, n] <= 6), 1, 0], {i, 1, n}, {j, 1, n}]]]; Table[an = a[n]; Print["a(", n, ") = ", an]; an, {n, 0, 16}] (* _Jean-François Alcover_, Jan 06 2016, adapted from Maple *)
%Y A260111 Cf. A000166, A260074, A260081, A260092, A260094, A260091, A260115, A257953, A260216.
%Y A260111 Cf. A259779.
%K A260111 nonn
%O A260111 0,4
%A A260111 _Alois P. Heinz_, Jul 16 2015