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 A003813 #18 Jun 14 2024 22:31:08
%S A003813 699612310033197642547200,124190524600592082795473760093457612800,
%T A003813 447244452196213365088128369288351077766266880000,
%U A003813 78616578542037111790447631835937500000000000000000000000,13191313011550511408913226688319815618147473583337425366223421440000
%N A003813 Order of simple Chevalley group A_8(q), q = prime power.
%D A003813 J. H. Conway, R. T. Curtis, S. P. Norton, R. A. Parker and R. A. Wilson, ATLAS of Finite Groups. Oxford Univ. Press, 1985 [for best online version see https://oeis.org/wiki/Welcome#Links_to_Other_Sites], p. xvi.
%D A003813 H. S. M. Coxeter and W. O. J. Moser, Generators and Relations for Discrete Groups, 4th ed., Springer-Verlag, NY, reprinted 1984, p. 131.
%F A003813 a(n) = a(A000961(n+1),8) where a(q,n) is defined in A003793. - _Sean A. Irvine_, Sep 18 2015
%t A003813 f[m_, n_] := Block[{g, x, y}, g[x_, y_] := x^(y (y + 1)/2) Product[x^k - 1, {k, 2, y + 1}]; g[m, n]/GCD[n + 1, m - 1]]; f[#, 8] & /@ Select[Range[2, 7], PrimePowerQ] (* _Michael De Vlieger_, Sep 18 2015 *)
%K A003813 nonn,easy
%O A003813 1,1
%A A003813 _N. J. A. Sloane_
%E A003813 a(5) from _Sean A. Irvine_, Sep 18 2015