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)).

1, 1, 4, 22, 266, 2218, 58100, 644828, 20949776, 502226904, 20622109728, 339816568512, 29770028441472, 568704136553760, 31544507027061120, 1864702918415957568, 150882403284582339072, 3672279699978976000896, 458988841789031457035136, 12369374876487501375431040

Offset

0,3

Links

Table of n, a(n) for n=0..19.

Prog

(PARI) a(n) = matpermanent(matrix(n, n, i, j, sigma(gcd(i, j))));

Crossrefs

Cf. A000142 (determinant), A134866 (matrix).

Sequence in context: A341459 A195227 A265908 * A119009 A326883 A317803

Adjacent sequences: A359108 A359109 A359110 * A359112 A359113 A359114

Keyword

nonn

Author

Michel Marcus, Dec 18 2022

Status

approved