A359111 - cp's OEIS frontend

A359111 a(n) is the permanent of the n X n matrix M(n) that is defined by M[i,j] = sigma(gcd(i,j)).

%I A359111 #13 Dec 19 2022 09:38:02
%S A359111 1,1,4,22,266,2218,58100,644828,20949776,502226904,20622109728,
%T A359111 339816568512,29770028441472,568704136553760,31544507027061120,
%U A359111 1864702918415957568,150882403284582339072,3672279699978976000896,458988841789031457035136,12369374876487501375431040
%N A359111 a(n) is the permanent of the n X n matrix M(n) that is defined by M[i,j] = sigma(gcd(i,j)).
%o A359111 (PARI) a(n) = matpermanent(matrix(n, n, i, j, sigma(gcd(i,j))));
%Y A359111 Cf. A000142 (determinant), A134866 (matrix).
%K A359111 nonn
%O A359111 0,3
%A A359111 _Michel Marcus_, Dec 18 2022

cp's OEIS Frontend

A359111 a(n) is the permanent of the n X n matrix M(n) that is defined by M[i,j] = sigma(gcd(i,j)).