A260094 - OEIS

%I #23 Jan 06 2016 12:24:25

%S 1,0,1,2,9,44,265,1854,14833,133496,1334961,14684570,59245120,

%T 238282730,956135652,3828509472,15296722436,60990443730,243596762752,

%U 975165838970,3913571754304,15742403448024,63428117376852,255662480209770,1031080275942464,4161127398011040

%N Number of permutations p of [n] with no fixed points and cyclic displacement of elements restricted by five: p(i)<>i and (i-p(i) mod n <= 5 or p(i)-i mod n <= 5).

%C a(n) = A000166(n) for n <= 11.

%p a:= n-> `if`(n=0, 1, LinearAlgebra[Permanent](Matrix(n, (i, j)->

%p         `if`(i<>j and (i-j mod n<=5 or j-i mod n<=5), 1, 0)))):

%p seq(a(n), n=0..15);

%t a[n_] := If[n == 0, 1, Permanent[Table[If[i != j && (Mod[i - j, n] <= 5 || Mod[j - i, n] <= 5), 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 Cf. A000166, A260074, A260081, A260092, A260111, A260091, A260115, A257953, A260216.

%Y Cf. A259778.

%K nonn

%O 0,4

%A _Alois P. Heinz_, Jul 15 2015