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 A262131 #4 Sep 11 2015 19:47:08 %S A262131 1,1,1,3,9,45,225,1575,11024,99216,891984,9811824,107544862, %T A262131 1398083206,18043262766,270648941490,4013029762464,68221505961888, %U A262131 1141412702224688,21686841342269072,403841897925538896,8480679856436316816,173881330973591388704 %N A262131 Number of permutations p of [n] such that the up-down signature of p has nonnegative partial sums with a maximal value <= 6. %H A262131 Alois P. Heinz, <a href="/A262131/b262131.txt">Table of n, a(n) for n = 0..200</a> %F A262131 a(n) = A262124(n,6). %Y A262131 Column k=6 of A262124. %K A262131 nonn %O A262131 0,4 %A A262131 _Alois P. Heinz_, Sep 11 2015