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 A032037 #23 Jul 30 2025 11:15:18
%S A032037 1,2,18,264,5400,141840,4551120,172529280,7545363840,373944211200,
%T A032037 20711190931200,1267784551756800,84991791159475200,
%U A032037 6193091146059417600,487361761916020992000,41192820513212239872000,3721763273059549605888000,357950394802026289815552000
%N A032037 Doubles (index 2+) under "AIJ" (ordered, indistinct, labeled) transform.
%H A032037 Andrew Howroyd, <a href="/A032037/b032037.txt">Table of n, a(n) for n = 1..200</a>
%H A032037 INRIA Algorithms Project, <a href="http://ecs.inria.fr/services/structure?nbr=92">Encyclopedia of Combinatorial Structures 92</a>.
%H A032037 Elena L. Wang and Guoce Xin, <a href="https://arxiv.org/abs/2507.15654">On Ward Numbers and Increasing Schröder Trees</a>, arXiv:2507.15654 [math.CO], 2025. See p. 12.
%F A032037 a(n) = n!*A001003(n-1). - _Vladeta Jovovic_, Dec 06 2002
%F A032037 E.g.f.: series reversion of x*(1-2*x)/(1-x). - _Andrew Howroyd_, Sep 19 2018
%F A032037 Assuming offset = 0:
%F A032037 a(n) = Sum_{k=0..n} Sum{m=0..k} (-1)^(m + k) * binomial(n + k, n + m) * binomial(n + m - 1, m - 1) * (n + m)! / m!. - _Peter Luschny_, Sep 26 2022
%t A032037 a[1]=1; a[2]=2; a[n_] := a[n]=3(2n-3)a[n-1]-(n-1)(n-3)a[n-2]
%o A032037 (PARI) Vec(serlaplace(serreverse(x*(1-2*x)/(1-x) + O(x^20)))) \\ _Andrew Howroyd_, Sep 19 2018
%K A032037 nonn
%O A032037 1,2
%A A032037 _Christian G. Bower_
%E A032037 Terms a(17) and beyond from _Andrew Howroyd_, Sep 19 2018