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 A026906 #14 Dec 25 2016 20:33:04 %S A026906 1,2,4,6,9,13,18,24,32,42,54,69,87,109,136,168,206,252,306,370,446, %T A026906 535,639,761,903,1068,1260,1482,1738,2034,2374,2764,3212,3724,4309, %U A026906 4977,5737,6601,7583,8696,9956,11382,12992,14808,16856 %N A026906 Number of sums S of distinct positive integers satisfying S <= n. %H A026906 Vaclav Kotesovec, <a href="/A026906/b026906.txt">Table of n, a(n) for n = 1..10000</a> %F A026906 a(n) ~ exp(Pi*sqrt(n/3)) * 3^(1/4) / (2*Pi*n^(1/4)) * (1 + (18+13*Pi^2) / (48*Pi*sqrt(3*n))). - _Vaclav Kotesovec_, Oct 25 2016 %F A026906 a(n) = A036469(n) - 1. - _Vaclav Kotesovec_, Oct 26 2016 %F A026906 G.f.: -1/(1 - x) + (1/(1 - x))*Product_{k>=1} (1 + x^k). - _Ilya Gutkovskiy_, Dec 25 2016 %e A026906 G.f. = x + 2*x^2 + 4*x^3 + 6*x^4 + 9*x^5 + 13*x^6 + 18*x^7 + 24*x^8 + 32*x^9 + ... %t A026906 Table[ Sum[ PartitionsQ[k], {k, 1, n}], {n, 1, 50}] %Y A026906 Partial sums of A000009. %Y A026906 Cf. A000070. %K A026906 nonn %O A026906 1,2 %A A026906 _Clark Kimberling_