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 A307761 #18 Jun 02 2019 04:35:33
%S A307761 1,3,7,11,16,21,29,35,43,48,56,65,79,87,97,99,103,111,134,156,182,190,
%T A307761 185,161,141,133,178,263,378,471,497,387,161,-133,-341,-313,75,782,
%U A307761 1645,2300,2379,1596,-42,-2222,-4232,-5241,-4464,-1551,3263,9023,14287,17249,16219,9912,-2074
%N A307761 L.g.f.: log(Product_{k>=1} (1 + x^k/(1 - x))) = Sum_{k>=1} a(k)*x^k/k.
%F A307761 Product {k>=1} (1 + x^k/(1 - x)) = exp(Sum_{k>=1} a(k)*x^k/k).
%e A307761 L.g.f.: L(x) = x/1 + 3*x^2/2 + 7*x^3/3 + 11*x^4/4 + 16*x^5/5 + 21*x^6/6 + 29*x^7/7 + 35*x^8/8 + ... .
%e A307761 exp(L(x)) = 1 + x + 2*x^2 + 4*x^3 + 7*x^4 + 12*x^5 + 20*x^6 + 33*x^7 + 53*x^8 + ... + A126348(n)*x^n + ... .
%o A307761 (PARI) N=66; x='x+O('x^N); Vec(x*deriv(log(prod(k=1, N, 1+x^k/(1-x)))))
%o A307761 (PARI) N=66; x='x+O('x^N); Vec(x*deriv(sum(k=1, N, x^k*sumdiv(k, d, (-1)^(d+1)/(d*(1-x)^d)))))
%Y A307761 Cf. A126348, A307674, A307675, A307762.
%K A307761 sign
%O A307761 1,2
%A A307761 _Seiichi Manyama_, Apr 27 2019