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 A174136 #2 Mar 30 2012 18:40:51 %S A174136 1,2,4,10,41,343,6327,249995,20536020,3445474030,1169394086932, %T A174136 798731069436512,1094825607339329108,3006942191342795594938, %U A174136 16533858553282474307626008,181924651566316766693192987410 %N A174136 Partial sums of A003087. %C A174136 Partial sums of number of acyclic digraphs with n unlabeled nodes; equivalently partial sums of the number of equivalence classes of n X n real (0,1)-matrices with all eigenvalues positive, up to conjugation by permutations. The subsequence of primes in this partial sum begins: 2, 41, no more through a(18). %F A174136 a(n) = SUM[i=0..n] A003087(i). %Y A174136 Cf. A003087, A003024. %K A174136 nonn %O A174136 0,2 %A A174136 _Jonathan Vos Post_, Mar 09 2010