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%I #19 Jul 25 2023 17:32:25
%S 0,0,0,1,5,15,35,71,126,215,330,511,715,1036,1370,1891,2380,3201,3876,
%T 5061,6020,7645,8855,11207,12655,15665,17676,21512,23751,29000,31465,
%U 37851,41250,48756,52400,62602,66045,77691,82966,96521,101270,118966,123410,143397
%N Expansion of Sum_{k>0} x^(4*k)/(1-x^k)^5.
%H Seiichi Manyama, <a href="/A363608/b363608.txt">Table of n, a(n) for n = 1..10000</a>
%F G.f.: Sum_{k>0} binomial(k,4) * x^k/(1 - x^k).
%F a(n) = Sum_{d|n} binomial(d,4).
%t a[n_] := DivisorSum[n, Binomial[#, 4] &]; Array[a, 50] (* _Amiram Eldar_, Jul 25 2023 *)
%o (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)))
%Y Cf. A000203, A069153, A363607.
%K nonn,easy
%O 1,5
%A _Seiichi Manyama_, Jun 11 2023
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