A369578 a(n) = [x^n] Product_{j=1..n, k=1..n} (1 + x^(k^j)).

1, 1, 2, 5, 13, 33, 81, 194, 458, 1074, 2513, 5876, 13722, 31961, 74168, 171395, 394450, 904393, 2066770, 4709538, 10704306, 24273709, 54926658, 124036675, 279559571, 628906790, 1412254773, 3165780760, 7084607367, 15828666526, 35309625162, 78648201835, 174927430681

Offset: 0

Author

Vaclav Kotesovec, Jan 26 2024

Keywords

• nonn

Links

• Vaclav Kotesovec, Table of n, a(n) for n = 0..1000

Crossrefs

Cf. A000009, A033461, A279329, A369575, A369570.

Programs

Mathematica

Table[SeriesCoefficient[Product[Product[1 + x^(k^j), {k, 1, n^(1/j)}], {j, 1, n}], {x, 0, n}], {n, 0, 40}]