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A363608
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Expansion of Sum_{k>0} x^(4*k)/(1-x^k)^5.
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4
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0, 0, 0, 1, 5, 15, 35, 71, 126, 215, 330, 511, 715, 1036, 1370, 1891, 2380, 3201, 3876, 5061, 6020, 7645, 8855, 11207, 12655, 15665, 17676, 21512, 23751, 29000, 31465, 37851, 41250, 48756, 52400, 62602, 66045, 77691, 82966, 96521, 101270, 118966, 123410, 143397
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OFFSET
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1,5
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LINKS
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FORMULA
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G.f.: Sum_{k>0} binomial(k,4) * x^k/(1 - x^k).
a(n) = Sum_{d|n} binomial(d,4).
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MATHEMATICA
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a[n_] := DivisorSum[n, Binomial[#, 4] &]; Array[a, 50] (* Amiram Eldar, Jul 25 2023 *)
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PROG
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(PARI) my(N=50, x='x+O('x^N)); concat([0, 0, 0], Vec(sum(k=1, N, x^(4*k)/(1-x^k)^5)))
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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STATUS
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approved
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