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 A034865 #27 Sep 08 2022 08:44:52
%S A034865 0,60,720,7560,80640,907200,10886400,139708800,1916006400,28021593600,
%T A034865 435891456000,7192209024000,125536739328000,2311968282624000,
%U A034865 44816615940096000,912338253066240000,19463216065413120000,434273008459530240000,10116006549998469120000
%N A034865 a(n) = n!*(n-4)/2.
%H A034865 Vincenzo Librandi, <a href="/A034865/b034865.txt">Table of n, a(n) for n = 4..200</a>
%H A034865 J. Riordan, <a href="http://dx.doi.org/10.1147/rd.45.0473">Enumeration of trees by height and diameter</a>, IBM J. Res. Dev. 4 (1960), 473-478.
%H A034865 <a href="/index/Fa#factorial">Index entries for sequences related to factorial numbers</a>
%F A034865 a(n) = 60 * A062199(n-5).
%F A034865 E.g.f.: x^5/(2*(1 - x)^2). - _Ilya Gutkovskiy_, May 23 2017
%t A034865 Table[n!*(n-4)/2,{n,4,30}] (* _Harvey P. Dale_, Apr 23 2012 *)
%o A034865 (Magma) [Factorial(n)*(n-4)/2: n in [4..22]]; // _Vincenzo Librandi_, May 25 2017
%o A034865 (PARI) x='x+O('x^30); concat([0], Vec(serlaplace(x^5/(2*(1-x)^2)))) \\ _G. C. Greubel_, Feb 16 2018
%K A034865 nonn
%O A034865 4,2
%A A034865 _N. J. A. Sloane_