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 A151581 #7 May 06 2020 01:37:57 %S A151581 0,9,5020,526240,26441856,862140162,21078701112,419567641380, %T A151581 7160621079552,108507581733075,1496470017336660,19127489390389332, %U A151581 229712892700188480,2619711824193741060,28608047711740408560,301155410573256748920,3072652643940279427584 %N A151581 Number of permutations of 1..n arranged in a circle with exactly 8 adjacent element pairs in decreasing order. %H A151581 Andrew Howroyd, <a href="/A151581/b151581.txt">Table of n, a(n) for n = 8..500</a> %F A151581 a(n) = n*A001244(n-1). - _Andrew Howroyd_, May 05 2020 %Y A151581 Column k=8 of A334218. %Y A151581 Cf. A001244. %K A151581 nonn %O A151581 8,2 %A A151581 _R. H. Hardin_, May 21 2009 %E A151581 Terms a(17) and beyond from _Andrew Howroyd_, May 05 2020