A382948 a(n) = [(x*y)^n] Product_{k>=1} (1 + x^k + y^k)^k.

1, 0, 2, 18, 50, 190, 536, 1644, 4432, 12876, 33560, 89118, 227734, 572578, 1409602, 3424996, 8150818, 19152532, 44455758, 101565172, 229712612, 513207144, 1134650028, 2481664146, 5379539720, 11545719858, 24574548632, 51855844492, 108559596182

Offset: 0

Author

Ilya Gutkovskiy, Apr 09 2025

Keywords

• nonn

Links

• Vaclav Kotesovec, Table of n, a(n) for n = 0..200

Crossrefs

Cf. A026007, A365662.

Programs

Mathematica

Table[SeriesCoefficient[Product[(1 + x^k + y^k)^k, {k, 1, n}], {x, 0, n}, {y, 0, n}], {n, 0, 28}]