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 A152506 #6 May 12 2020 12:55:38
%S A152506 0,1,3277,2483739,1156102209,443469188267,156475306087585,
%T A152506 53194863262703203,17785402102372820321,5902647043581987876939,
%U A152506 1952635794694419540863057,645038537405519790637628675,212955626342843141187623423793,70288152907297654332280282998411
%N A152506 1/5 of the number of permutations of 4 indistinguishable copies of 1..n with exactly 4 local maxima.
%H A152506 Andrew Howroyd, <a href="/A152506/b152506.txt">Table of n, a(n) for n = 1..200</a>
%o A152506 (PARI) \\ PeaksBySig defined in A334774.
%o A152506 a(n) = {PeaksBySig(vector(n,i,4), [3])[1]/5} \\ _Andrew Howroyd_, May 12 2020
%Y A152506 Cf. A152504, A334774.
%K A152506 nonn
%O A152506 1,3
%A A152506 _R. H. Hardin_, Dec 06 2008
%E A152506 Terms a(8) and beyond from _Andrew Howroyd_, May 12 2020