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 A293784 #19 Oct 21 2017 11:09:52 %S A293784 1,1,2,6,24,120,720,5040,35214,229378,1408522,8370900,49154431, %T A293784 288653307,1703668022,10115769088,60332300930,360602808068, %U A293784 2156022737216,12883491408374,76929443106701,459100718065735,2739019173150040,16339850317888878,97481064340012333 %N A293784 Number of permutations of length n sortable by 6 passes through a pop-stack. %H A293784 Bjarki Ágúst Guðmundsson, <a href="/A293784/b293784.txt">Table of n, a(n) for n = 0..1000</a> %H A293784 Anders Claesson, Bjarki Ágúst Guðmundsson, <a href="https://arxiv.org/abs/1710.04978">Enumerating permutations sortable by k passes through a pop-stack</a>, arXiv:1710.04978 [math.CO], 2017. %H A293784 Bjarki Ágúst Guðmundsson, <a href="/A293784/a293784.txt">generating function</a>. %H A293784 Bjarki Ágúst Guðmundsson, <a href="/A293784/a293784.gp.txt">PARI script</a>. %Y A293784 Cf. A224232, A293774, A293775, A293776. %K A293784 nonn,easy %O A293784 0,3 %A A293784 _Bjarki Ágúst Guðmundsson_, Oct 16 2017