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 A174146 #7 Apr 19 2018 10:36:16
%S A174146 1,2,5,13,40,131,481,1857,7600,32235,141203,633383,2899885,13498337,
%T A174146 63734268,304606922,1471339736,7173341171,35262128485,174617051093,
%U A174146 870425605393,4364815662605,22006511124267,111501534635143,567511427859428,2900508758069868
%N A174146 Partial sums of A000238.
%C A174146 Partial sums of number of oriented trees with n nodes. The subsequence of primes in this partial sum begins: 2, 5, 13, 131, 633383, 870425605393, 55532683410408578237, 290078510058531496879, 26098901136734259174974296003.
%H A174146 Alois P. Heinz, <a href="/A174146/b174146.txt">Table of n, a(n) for n = 1..1000</a>
%F A174146 a(n) = Sum_{i=1..n} A000238(i).
%e A174146 a(32) = 1 + 1 + 3 + 8 + 27 + 91 + 350 + 1376 + 5743 + 24635 + 108968 + 492180 + 2266502 + 10598452 + 50235931 + 240872654 + 1166732814 + 5702001435 + 28088787314 + 139354922608 + 695808554300 + 3494390057212 + 17641695461662 + 89495023510876 + 456009893224285 + 2332997330210440 + 11980753878699716 + 61739654323377296 + 319188605907760846 + 1655151350788152551 + 8606939469625111036 + 44874783067127406924.
%Y A174146 Cf. A000238.
%K A174146 nonn
%O A174146 1,2
%A A174146 _Jonathan Vos Post_, Mar 09 2010