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 A173489 #13 Aug 28 2020 06:16:49
%S A173489 1,2,4,10,32,133,706,4542,33770,284519,2694100,28292286,324935676,
%T A173489 4052477864,54679031852,793359552994,12294933375782,202713354823112,
%U A173489 3547535843321377,65667058958304601,1280634899889213903
%N A173489 Partial sums of A000140.
%F A173489 a(n) = Sum_{i=1..n} A000140(i).
%F A173489 a(n) ~ 6 * n^(n-1) / exp(n). - _Vaclav Kotesovec_, Oct 27 2016
%t A173489 f[n_] := Max@ CoefficientList[ Expand@ Product[ Sum[x^i, {i, 0, j}], {j, n - 1}], x]; Accumulate@ Array[f, 21]
%Y A173489 Cf. A000140.
%K A173489 easy,nonn
%O A173489 1,2
%A A173489 _Jonathan Vos Post_, Feb 19 2010
%E A173489 a(15) corrected by _Georg Fischer_, Aug 28 2020