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 A134826 #6 Sep 25 2024 09:46:06
%S A134826 1,4,14,58,214,908,3442,14444,56386,234476,920490,3847998,15165982,
%T A134826 62944212,250787568,1036586952,4132605038,17106500792,68303652958,
%U A134826 281749732730,1130378730046,4648910236412,18657451711020,76808828008438
%N A134826 Row sums of triangle A134285, called s2(3)'.
%F A134826 a(n) = Sum_{m=1..n} A134285(n,m), n>=1.
%Y A134826 Cf. A134827 (alternating row sums of triangle A134285).
%K A134826 nonn,easy
%O A134826 1,2
%A A134826 _Wolfdieter Lang_, Nov 13 2007