A373030 Expansion of 1 + Sum_{i>=1} Sum_{j>=1} x^(i*j) * Product_{k=1..i*j-1} (1+x^k).

1, 1, 2, 4, 5, 7, 11, 14, 17, 24, 30, 37, 48, 58, 71, 92, 108, 129, 160, 188, 225, 273, 319, 377, 449, 524, 612, 721, 836, 969, 1134, 1305, 1503, 1742, 1996, 2291, 2637, 3008, 3435, 3929, 4469, 5076, 5778, 6541, 7401, 8393, 9466, 10676, 12049, 13550, 15235, 17128

Offset

0,3

Links

Table of n, a(n) for n=0..51.

Formula

G.f.: 1 + Sum_{k>=1} A000005(k) * x^k * Product_{j=1..k-1} (1+x^j).

Crossrefs

Row sums of A373029.

Cf. A000005, A000009, A323433.

Sequence in context: A097581 A090614 A171022 * A097697 A035620 A363045

Adjacent sequences: A373027 A373028 A373029 * A373031 A373032 A373033

Keyword

nonn

Author

Seiichi Manyama, May 20 2024

Status

approved