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 A279293 #6 Dec 22 2020 03:12:27 %S A279293 1,12,316,4961,88482,1456780,24970807,430069638,7646066285, %T A279293 139512608803,2630205520242,51191324887317,1030225266241718, %U A279293 21431850533761458,460916811387051427,10243049068068285706,235127217600172319772,5571780677576178939683 %N A279293 Number of permutations of [n] having exactly four (possibly overlapping) doubledescents. %H A279293 Alois P. Heinz, <a href="/A279293/b279293.txt">Table of n, a(n) for n = 6..461</a> %F A279293 a(n) ~ c * 3^(3*n/2) * n^(n + 9/2) / (exp(n) * 2^n * Pi^n), where c = 0.000357063672536829943422824320618... . - _Vaclav Kotesovec_, Dec 22 2020 %Y A279293 Column k=4 of A162975. %K A279293 nonn %O A279293 6,2 %A A279293 _Alois P. Heinz_, Dec 09 2016