A337990 -id:A337990 - cp's OEIS frontend

1, 2, 20, 26426, 61390791862967, 769671787836269530451291677988751813890576

Offset: 0

Ilya Gutkovskiy, Jul 23 2021

The next term is too large to include.

Table[SeriesCoefficient[1/(1 - Sum[x^(3^k), {k, 0, n}]), {x, 0, 3^n}], {n, 0, 5}]

a(n) = [x^(3^n)] 1 / (1 - Sum_{k>=0} x^(3^k)).

1, 2, 96, 579739960, 773527571233557154337704151068262296

Offset: 0

Ilya Gutkovskiy, Jul 23 2021

The next term is too large to include.

Table[SeriesCoefficient[1/(1 - Sum[x^(4^k), {k, 0, n}]), {x, 0, 4^n}], {n, 0, 4}]

a(n) = [x^(4^n)] 1 / (1 - Sum_{k>=0} x^(4^k)).

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