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 A167558 #14 Jun 16 2016 03:10:42
%S A167558 1,12,160,2688,55296,1351680,38338560,1238630400,44920995840,
%T A167558 1807409479680,79906524364800,3850733459865600,200907832688640000,
%U A167558 11282983883794022400,678650586195610828800,43527244493925384192000
%N A167558 The second right hand column of triangle A167557.
%C A167558 Triangle A167557 is the lower left triangle of the ED1 array A167546.
%H A167558 G. C. Greubel, <a href="/A167558/b167558.txt">Table of n, a(n) for n = 2..150</a>
%H A167558 A. Ryabov, P. Chvosta, <a href="http://arxiv.org/abs/1402.1949">Tracer dynamics in a single-file system with absorbing boundary</a>, arXiv preprint arXiv:1402.1949 [cond-mat.stat-mech], 2014.
%F A167558 a(n) = 4^(n-2)*(n-2)!*(2*n-3)!/(2*n-4)!.
%F A167558 (-2*n+5)*a(n) +4*(2*n-3)*(n-2)*a(n-1)=0. - _R. J. Mathar_, Apr 01 2015
%t A167558 Table[4^(n-2) (n-2)! (2n-3)!/(2n-4)!,{n,2,20}] (* _Harvey P. Dale_, Aug 21 2013 *)
%Y A167558 A167546 is the ED1 array.
%Y A167558 Equals the second right hand column of triangle A167557.
%K A167558 easy,nonn
%O A167558 2,2
%A A167558 _Johannes W. Meijer_, Nov 10 2009