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A292424 a(n) = [x^n] Product_{k=1..n} 1/((1 - x)^k * (1 - x^k)). 1
1, 2, 11, 92, 1080, 16490, 311238, 7007796, 183431836, 5474465390, 183502419505, 6825981504602, 279041903645153, 12434720809043056, 599929817745490600, 31155278025923406979, 1732781419647450834768, 102761486514549541577999, 6473124665688520200808139 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Vaclav Kotesovec, Table of n, a(n) for n = 0..368

FORMULA

a(n) ~ exp(n+2) * n^(n-1/2) / (sqrt(Pi) * 2^(n+1/2)).

MATHEMATICA

Table[SeriesCoefficient[Product[1/((1-x)^k * (1-x^k)), {k, 1, n}], {x, 0, n}], {n, 0, 20}]

Table[SeriesCoefficient[Product[1/(1-x^k), {k, 1, n}] / (1-x)^(n*(n+1)/2), {x, 0, n}], {n, 0, 20}]

CROSSREFS

Cf. A292613.

Sequence in context: A047854 A222080 A122708 * A225623 A005366 A068392

Adjacent sequences:  A292421 A292422 A292423 * A292425 A292426 A292427

KEYWORD

nonn

AUTHOR

Vaclav Kotesovec, Sep 20 2017

STATUS

approved

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Last modified November 17 06:35 EST 2018. Contains 317275 sequences. (Running on oeis4.)