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 A306749 #35 May 14 2021 02:53:56
%S A306749 1,1,1,0,0,-1,1,-1,2,-2,2,-4,6,-8,11,-13,16,-23,32,-44,61,-80,102,
%T A306749 -133,178,-243,331,-441,579,-759,1001,-1335,1792,-2398,3186,-4205,
%U A306749 5537,-7320,9734,-12975,17266,-22893,30267,-40004,52968,-70282,93348,-123900,164179,-217277
%N A306749 Expansion of Product_{k>=1} 1/(1 - x^k * (1 - x)).
%H A306749 Seiichi Manyama, <a href="/A306749/b306749.txt">Table of n, a(n) for n = 0..1000</a>
%F A306749 G.f.: exp(Sum_{k>=1} x^k * Sum_{d|k} (1 - x)^d/d). - _Ilya Gutkovskiy_, Apr 16 2019
%t A306749 m = 49; CoefficientList[Series[Product[1/(1 - x^k * (1 - x)), {k, 1, m}], {x, 0, m}], x] (* _Amiram Eldar_, May 14 2021 *)
%o A306749 (PARI) N=66; x='x+O('x^N); Vec(1/prod(k=1, N, 1-x^k*(1-x)))
%Y A306749 Cf. A152398, A227681, A306691.
%K A306749 sign
%O A306749 0,9
%A A306749 _Seiichi Manyama_, Apr 16 2019