A283224 Expansion of exp( Sum_{n>=1} sigma_2(2*n)*x^n/n ) in powers of x.

1, 5, 23, 90, 317, 1036, 3192, 9358, 26336, 71542, 188440, 483007, 1208275, 2956941, 7093531, 16709523, 38706389, 88281394, 198474497, 440263342, 964424210, 2087882510, 4470194335, 9471079495, 19868723042, 41291454537, 85049747913, 173697766646

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(2*k)*a(n-k). - Seiichi Manyama, Mar 04 2017

Crossrefs

Cf. exp( Sum_{n>=1} sigma_k(2*n)*x^n/n ): A182818 (k=1), this sequence (k=2).

Cf. exp( Sum_{n>=1} sigma_2(m*n)*x^n/n ): A000219 (m=1), this sequence (m=2), A283238 (m=3).

Sequence in context: A121329 A246175 A362764 * A178834 A331720 A327973

Adjacent sequences: A283221 A283222 A283223 * A283225 A283226 A283227

Keyword

nonn

Author

Seiichi Manyama, Mar 03 2017

Status

approved