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