A032304 "EFK" (unordered, size, unlabeled) transform of 1,3,5,7,...

1, 1, 3, 8, 12, 31, 56, 107, 168, 372, 620, 1032, 1819, 2888, 5228, 8821, 13692, 21764, 36528, 54756, 92384, 145180, 222809, 339596, 524468, 803716, 1204461, 1884224, 2844820, 4202784, 6291608, 9287236, 13623388, 20316140, 29251828, 43892909, 64068484, 92248760

Offset

0,3

Links

Andrew Howroyd, Table of n, a(n) for n = 0..1000

C. G. Bower, Transforms (2)

Formula

G.f.: Product{k >= 1} (1 + (2*k-1)*x^k).

Prog

(PARI) seq(n)={Vec(prod(k=1, n, 1 + (2*k-1)*x^k + O(x*x^n)))} \\ Andrew Howroyd, Sep 20 2018

Crossrefs

Sequence in context: A058582 A178720 A027292 * A032217 A032142 A032046

Adjacent sequences: A032301 A032302 A032303 * A032305 A032306 A032307

Keyword

nonn

Author

Christian G. Bower

Extensions

a(0)=1 prepended and terms a(33) and beyond from Andrew Howroyd, Sep 20 2018

Status

approved