A307323 Expansion of Product_{j>=1} (1 + (-1 + Product_{k>=1} (1 + x^k)^k)^j)^j.

1, 1, 4, 18, 74, 303, 1206, 4741, 18466, 71463, 274879, 1051509, 4001727, 15157935, 57170668, 214787989, 804049797, 2999846236, 11156943967, 41370989836, 152973793900, 564117250793, 2074959664189, 7613615954760, 27871659379578, 101805487967357, 371072295698710

Offset

0,3

Links

Table of n, a(n) for n=0..26.

Formula

G.f.: g(g(x) - 1), where g(x) = g.f. of A026007.

Mathematica

nmax = 26; CoefficientList[Series[Product[(1 + (-1 + Product[(1 + x^k)^k, {k, 1, nmax}])^j)^j, {j, 1, nmax}], {x, 0, nmax}], x]

Crossrefs

Cf. A026007, A307128, A307321.

Sequence in context: A075675 A047034 A266753 * A218059 A069008 A026560

Adjacent sequences: A307320 A307321 A307322 * A307324 A307325 A307326

Keyword

nonn

Author

Ilya Gutkovskiy, Apr 02 2019

Status

approved