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 A288543 #5 Jun 12 2017 11:38:40 %S A288543 1,0,0,0,0,5,56,240,620,1220,2201,4501,14231,67597,332768,1455695, %T A288543 5611277,19525749,63217514,197236391,617466587,2015606482,7005348816, %U A288543 25768091554,97973413377,375778678054,1431049415936,5374397862025,19899453137028,72900123590938 %N A288543 Number of Dyck paths of semilength n such that the minimal number of peaks over all positive levels equals four. %H A288543 Alois P. Heinz, <a href="/A288543/b288543.txt">Table of n, a(n) for n = 4..300</a> %H A288543 Wikipedia, <a href="https://en.wikipedia.org/wiki/Lattice_path#Counting_lattice_paths">Counting lattice paths</a> %Y A288543 Column k=4 of A288387. %Y A288543 Cf. A000108. %K A288543 nonn %O A288543 4,6 %A A288543 _Alois P. Heinz_, Jun 11 2017