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 A336979 #20 May 01 2021 17:43:36
%S A336979 1,1,3,6,11,21,37,69,108,192,312,522,827,1297,2032,3240,4982,7569,
%T A336979 11508,17107,25696,38340,57080,83298,121373,175653,253455,364307,
%U A336979 523650,747487,1063375,1498471,2106317,2955154,4124071,5750547,8000706,11104596,15324290,21093106
%N A336979 Expansion of Product_{k>=1} (1 + x^k * (k + x)).
%H A336979 Seiichi Manyama, <a href="/A336979/b336979.txt">Table of n, a(n) for n = 0..1000</a>
%F A336979 G.f.: exp(Sum_{k>=1} x^k * Sum_{d|k} (-1)^(d+1) * (k/d + x)^d / d).
%t A336979 m = 39; CoefficientList[Series[Product[1 + x^k*(k + x), {k, 1, m}], {x, 0, m}], x] (* _Amiram Eldar_, May 01 2021 *)
%o A336979 (PARI) N=66; x='x+O('x^N); Vec(prod(k=1, N, 1+x^k*(k+x)))
%o A336979 (PARI) N=66; x='x+O('x^N); Vec(exp(sum(k=1, N, x^k*sumdiv(k, d, (-1)^(d+1)*(k/d+x)^d/d))))
%Y A336979 Cf. A022629, A160571, A336975, A336976, A336977, A336978, A336980.
%K A336979 nonn
%O A336979 0,3
%A A336979 _Seiichi Manyama_, Aug 09 2020