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 A333045 #14 Mar 08 2020 10:15:52 %S A333045 1,2,2,4,8,10,14,24,34,44,62,86,116,156,206,274,362,462,598,782,994, %T A333045 1258,1606,2018,2528,3178,3952,4904,6094,7490,9194,11322,13834,16836, %U A333045 20518,24880,30086,36366,43792,52656,63250,75626,90344,107926,128422,152546 %N A333045 Expansion of Product_{k>=1} (1 + x^sigma(k)) / (1 - x^sigma(k)). %C A333045 Convolution of A111865 and A305321. %t A333045 nmax = 50; CoefficientList[Series[Product[(1 + x^DivisorSigma[1, k])/(1 - x^DivisorSigma[1, k]), {k, 1, nmax}], {x, 0, nmax}], x] %Y A333045 Cf. A000203, A111865, A305321. %K A333045 nonn %O A333045 0,2 %A A333045 _Vaclav Kotesovec_, Mar 06 2020