A298730 - OEIS

A298730

Expansion of Product_{k>=1} 1/(1 - x^(k*(k+1)/2))^(k*(k+1)/2).

1, 1, 1, 4, 4, 4, 16, 16, 16, 44, 54, 54, 126, 156, 156, 315, 435, 435, 780, 1060, 1115, 1856, 2576, 2741, 4214, 5804, 6464, 9446, 12924, 14464, 20324, 27818, 31778, 43166, 58232, 66977, 89396, 120000, 139255, 181274, 240405, 282000, 362457, 476334, 560709, 708893, 924923, 1096773, 1372597

(list; graph; refs; listen; history; text; internal format)

OFFSET

0,4

LINKS

Table of n, a(n) for n=0..48.

FORMULA

G.f.: Product_{k>=1} 1/(1 - x^A000217(k))^A000217(k).

MATHEMATICA

nmax = 48; CoefficientList[Series[Product[1/(1 - x^(k (k + 1)/2))^(k (k + 1)/2), {k, 1, nmax}], {x, 0, nmax}], x]

CROSSREFS

Cf. A000217, A000294, A007294, A291655, A298850.

Sequence in context: A223824 A218056 A218651 * A218181 A231586 A231700

Adjacent sequences: A298727 A298728 A298729 * A298731 A298732 A298733

KEYWORD

nonn

AUTHOR

Ilya Gutkovskiy, Mar 09 2018

STATUS

approved