cp's OEIS Frontend

A257953 Number of permutations p of [n] with no fixed points and cyclic displacement of elements restricted by nine: p(i)<>i and (i-p(i) mod n <= 9 or p(i)-i mod n <= 9).

%I A257953 #44 Jan 06 2016 12:09:43
%S A257953 1,0,1,2,9,44,265,1854,14833,133496,1334961,14684570,176214841,
%T A257953 2290792932,32071101049,481066515734,7697064251745,130850092279664,
%U A257953 2355301661033953,44750731559645106,312426715251262464,2178674876680100744,15178362413058474596,105663183116236278362
%N A257953 Number of permutations p of [n] with no fixed points and cyclic displacement of elements restricted by nine: p(i)<>i and (i-p(i) mod n <= 9 or p(i)-i mod n <= 9).
%C A257953 a(n) = A000166(n) for n <= 19.
%p A257953 a:= n-> `if`(n=0, 1, LinearAlgebra[Permanent](Matrix(n, (i, j)->
%p A257953         `if`(i<>j and (i-j mod n<=9 or j-i mod n<=9), 1, 0)))):
%p A257953 seq(a(n), n=0..20);
%t A257953 a[n_] := If[n == 0, 1, Permanent[Table[If[i != j && (Mod[i - j, n] <= 9 || Mod[j - i, n] <= 9), 1, 0], {i, 1, n}, {j, 1, n}]]]; Table[an = a[n]; Print["a(", n, ") = ", an]; an, {n, 0, 20}] (* _Jean-François Alcover_, Jan 06 2016, adapted from Maple *)
%Y A257953 Cf. A000166, A260074, A260081, A260092, A260094, A260111, A260091, A260115, A260216.
%Y A257953 Cf. A259782.
%K A257953 nonn
%O A257953 0,4
%A A257953 _Alois P. Heinz_, Jul 19 2015