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A329156
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Expansion of Product_{k>=1} 1 / (1 - Sum_{j>=1} j * x^(k*j)).
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2
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1, 1, 4, 10, 29, 72, 200, 510, 1364, 3546, 9348, 24400, 64090, 167562, 439200, 1149360, 3010349, 7879832, 20633304, 54014950, 141422328, 370239300, 969323000, 2537696160, 6643839400, 17393731933, 45537549048, 119218684970, 312119004990, 817137724392, 2139295489200, 5600747143950
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OFFSET
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0,3
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COMMENTS
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LINKS
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FORMULA
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G.f.: Product_{k>=1} 1 / (1 - x^k / (1 - x^k)^2).
G.f.: exp(Sum_{k>=1} ( Sum_{d|k} 1 / (d * (1 - x^(k/d))^(2*d)) ) * x^k).
G.f.: Product_{k>=1} 1 / (1 - x^k)^A032198(k).
G.f.: A(x) = Product_{k>=1} B(x^k), where B(x) = g.f. of A088305.
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MATHEMATICA
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nmax = 31; CoefficientList[Series[Product[1/(1 - Sum[j x^(k j), {j, 1, nmax}]), {k, 1, nmax}], {x, 0, nmax}], x]
nmax = 31; CoefficientList[Series[Product[1/(1 - x^k/(1 - x^k)^2), {k, 1, nmax}], {x, 0, nmax}], x]
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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