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 A336283 #10 Jul 16 2020 11:48:29 %S A336283 1,3,20,152,1264,11168,102976,979840,9550592,94876160,957101056, %T A336283 9778354176,100970557440,1052097552384,11048512143360,116814955118592, %U A336283 1242454765535232,13284730164346880,142713773337346048,1539605733158944768 %N A336283 Row sums of A192933. %C A336283 a(n) is the total number of bimonotone subdivisions of a 2-row grid with n points on the top row and k points at the bottom row for k from 1 to n. See Robeva and Sun (2020) for more details. (The authors do not seem to care about the value of a(1) because they do not consider subdivisions of a degenerate polygon with only one side.) %H A336283 Elina Robeva and Melinda Sun, <a href="https://arxiv.org/abs/2007.00877">Bimonotone Subdivisions of Point Configurations in the Plane</a>, arXiv:2007.00877 [math.CO], 2020. %F A336283 O.g.f.: x*(1-x)*(2*g(2*x) - 1), where g(x) is the o.g.f. of A001003. %F A336283 a(n) = 2^n*A001003(n-1) - 2^(n-1)*A001003(n-2) for n >= 3. %o A336283 (PARI) lista(nn) = {my(T=matrix(nn, nn)); T[1, 1] = 1; for (n=2, nn, for (k=1, n, T[n, k] = sum(i=1, n, sum(j=1, k, if ((i!=n) || (j!=k), T[i, j]))); ); ); vector(nn, k, vecsum(vector(k, i, T[k, i]))); } \\ _Michel Marcus_, Jul 16 2020 %Y A336283 Cf. A001003, A192933. %K A336283 nonn %O A336283 1,2 %A A336283 _Petros Hadjicostas_, Jul 15 2020