This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A363618 #17 Jul 25 2023 16:37:51
%S A363618 0,0,0,1,-5,15,-35,71,-126,205,-330,511,-715,966,-1370,1891,-2380,
%T A363618 2949,-3876,5051,-6020,6985,-8855,11207,-12655,14235,-17676,21442,
%U A363618 -23751,26260,-31465,37851,-41250,43996,-52400,62350,-66045,69939,-82966,96511,-101270
%N A363618 Expansion of Sum_{k>0} x^(4*k)/(1+x^k)^5.
%H A363618 Seiichi Manyama, <a href="/A363618/b363618.txt">Table of n, a(n) for n = 1..10000</a>
%F A363618 G.f.: Sum_{k>0} binomial(k,4) * (-x)^k/(1 - x^k).
%F A363618 a(n) = Sum_{d|n} (-1)^d * binomial(d,4).
%t A363618 a[n_] := DivisorSum[n, (-1)^# * Binomial[#, 4] &]; Array[a, 50] (* _Amiram Eldar_, Jul 25 2023 *)
%o A363618 (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)))
%o A363618 (PARI) a(n) = sumdiv(n, d, (-1)^d*binomial(d, 4));
%Y A363618 Cf. A363022, A363617.
%Y A363618 Cf. A363608.
%K A363618 sign
%O A363618 1,5
%A A363618 _Seiichi Manyama_, Jun 11 2023