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 A100938 #7 May 11 2014 05:07:28
%S A100938 1,2,5,10,22,46,97,200,412,844,1729,3536,7227,14754,30093,61312,
%T A100938 124782,253664,515085,1044796,2117158,4286330,8671103,17529304,
%U A100938 35416016,71518510,144362774,291299094,587617054,1185060666,2389424213
%N A100938 Self-convolution of A092684.
%C A100938 A092684 is the leftmost column of triangle A092683.
%F A100938 a(n) = 1 + Sum_{k=1..n} Sum_{j=0..n-k} binomial(k, j)*a(j).
%o A100938 (PARI) {a(n)=1+sum(k=1,n,sum(j=0,n-k,binomial(k,j)*a(j)))}
%Y A100938 Cf. A092684, A092683.
%K A100938 nonn
%O A100938 0,2
%A A100938 _Paul D. Hanna_, Nov 23 2004