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 A307548 #16 May 14 2021 02:53:03
%S A307548 1,-1,0,1,-2,4,-9,21,-48,105,-218,429,-803,1442,-2521,4380,-7734,
%T A307548 14091,-26468,50405,-94980,172824,-296704,467589,-644459,678109,
%U A307548 -177123,-1752141,7003180,-19432494,46778567,-104623822,224830880,-473859273,992825436,-2084921584
%N A307548 Expansion of Product_{k>=1} (1 - (x/(1+x))^k).
%F A307548 O.g.f.: Sum_{n >= 0} (-1)^n * x^(n*(n+1)/2)/Product_{k = 1..n} ((1 + x)^k - x^k). Cf. A320591. - _Peter Bala_, Dec 22 2020
%t A307548 m = 35; CoefficientList[Series[Product[1 - (x/(1+x))^k, {k, 1, m}], {x, 0, m}], x] (* _Amiram Eldar_, May 14 2021 *)
%o A307548 (PARI) N=66; x='x+O('x^N); Vec(prod(k=1, N, 1-(x/(1+x))^k))
%Y A307548 Convolution inverse of A320590.
%Y A307548 Cf. A129519, A307310, A320591.
%K A307548 sign,easy
%O A307548 0,5
%A A307548 _Seiichi Manyama_, Apr 14 2019