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A260092 Number of permutations p of [n] with no fixed points and cyclic displacement of elements restricted by four: p(i)<>i and (i-p(i) mod n <= 4 or p(i)-i mod n <= 4).

%I A260092 #18 Jan 06 2016 12:24:33
%S A260092 1,0,1,2,9,44,265,1854,14833,133496,440192,1445100,4728000,15405008,
%T A260092 49955280,162442816,530284304,1738077424,5714461760,18795784436,
%U A260092 61868602624,203858323008,672535917712,2221505855492,7345985276816,24314075406208,80542683435168
%N A260092 Number of permutations p of [n] with no fixed points and cyclic displacement of elements restricted by four: p(i)<>i and (i-p(i) mod n <= 4 or p(i)-i mod n <= 4).
%C A260092 a(n) = A000166(n) for n <= 9.
%p A260092 a:= n-> `if`(n=0, 1, LinearAlgebra[Permanent](Matrix(n, (i, j)->
%p A260092         `if`(i<>j and (i-j mod n<=4 or j-i mod n<=4), 1, 0)))):
%p A260092 seq(a(n), n=0..15);
%t A260092 a[n_] := If[n == 0, 1, Permanent[Table[If[i != j && (Mod[i - j, n] <= 4 || Mod[j - i, n] <= 4), 1, 0], {i, 1, n}, {j, 1, n}]]]; Table[an = a[n]; Print["a(", n, ") = ", an]; an, {n, 0, 15}] (* _Jean-François Alcover_, Jan 06 2016, adapted from Maple *)
%Y A260092 Cf. A000166, A260074, A260081, A260094, A260111, A260091, A260115, A257953, A260216.
%Y A260092 Cf. A259777.
%K A260092 nonn
%O A260092 0,4
%A A260092 _Alois P. Heinz_, Jul 15 2015