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 A327940 #4 Oct 06 2019 03:56:17
%S A327940 1,0,1,2,9,44,385,1854,23233,153656,2151441,18787130,338487721,
%T A327940 3165541092,60609811249,835202858294,14913805143105,228441779869424,
%U A327940 5319673396479073,81040768940877426,2153026504862728201,39759334398324543260,988919906784578473761
%N A327940 Expansion of e.g.f. exp(Sum_{i>=1} Sum_{j=1..i-1} x^(i*j) / (i*j)).
%F A327940 E.g.f.: exp(Sum_{k>=1} floor(A000005(k)/2) * x^k / k).
%F A327940 E.g.f.: exp(Sum_{k>=1} A056924(k) * x^k / k).
%F A327940 E.g.f.: Product_{k>=1} 1 / (1 - x^A026424(k))^(1/A026424(k)).
%t A327940 nmax = 22; CoefficientList[Series[Exp[Sum[Floor[DivisorSigma[0, k]/2] x^k/k, {k, 1, nmax}]], {x, 0, nmax}], x] Range[0, nmax]!
%t A327940 a[n_] := a[n] = If[n == 0, 1, Sum[Floor[DivisorSigma[0, k]/2] a[n - k], {k, 1, n}]/n]; Table[n! a[n], {n, 0, 22}]
%Y A327940 Cf. A000005, A026424, A028342, A056924, A206303, A327927.
%K A327940 nonn
%O A327940 0,4
%A A327940 _Ilya Gutkovskiy_, Sep 30 2019