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 A180166 #5 Apr 13 2021 18:46:39
%S A180166 1,3,7,18,51,161,560,2123,8691,38142,178407,885041,4636948,25564727,
%T A180166 147848651,894448186,5646589363,37115577265,253517232120,
%U A180166 1796241061843,13180234725987,100009217354694,783656713398383,6333420109604593,52732283687195340,451831859926030943
%N A180166 Row sums of triangle A180165.
%H A180166 Andrew Howroyd, <a href="/A180166/b180166.txt">Table of n, a(n) for n = 1..500</a>
%F A180166 G.f.: Sum_{k>=1} x^k*(1 + x)/(1 - k*x - k*x^2). - _Andrew Howroyd_, Apr 13 2021
%e A180166 a(5) = 151 = sum of row 5 terms of triangle A180165: (1 + 5 + 15 + 22 + 8).
%o A180166 (PARI) seq(n)={Vec(sum(k=1, n, x^k*(1+x)/(1-k*x-k*x^2) + O(x*x^n)))} \\ _Andrew Howroyd_, Apr 13 2021
%Y A180166 Row sums of A180165.
%K A180166 nonn
%O A180166 1,2
%A A180166 _Gary W. Adamson_, Aug 14 2010
%E A180166 a(8) and a(11) corrected and a(14) and beyond from _Andrew Howroyd_, Apr 13 2021