A283238 Expansion of exp( Sum_{n>=1} sigma_2(3*n)*x^n/n ) in powers of x.

1, 10, 75, 447, 2335, 10977, 47667, 193775, 745819, 2738568, 9653342, 32821384, 108061167, 345622069, 1076767956, 3275039352, 9743874779, 28405248949, 81256123017, 228383836091, 631427595230, 1718990010867, 4612234492354, 12206598044861, 31889379237288

Offset

0,2

Links

Seiichi Manyama, Table of n, a(n) for n = 0..1000

Formula

a(n) = (1/n)*Sum_{k=1..n} sigma_2(3*k)*a(n-k). - Seiichi Manyama, Mar 04 2017

Crossrefs

Cf. exp( Sum_{n>=1} sigma_k(3*n)*x^n/n ): A182819 (k=1), this sequence (k=2).

Cf. exp( Sum_{n>=1} sigma_2(m*n)*x^n/n ): A000219 (m=1), A283224 (m=2), this sequence (m=3).

Sequence in context: A026979 A274251 A073379 * A316462 A022734 A027203

Adjacent sequences: A283235 A283236 A283237 * A283239 A283240 A283241

Keyword

nonn

Author

Seiichi Manyama, Mar 03 2017

Status

approved