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 A003805 #16 Jun 14 2024 22:31:08
%S A003805 5348063769211699200,961721214905722855895197286400,
%T A003805 78099458182389588115529148326215680000,
%U A003805 103044374585338670859375000000000000000000000,170115000551935077294273059250893063598899496222720000,770654129255561941216424578913668563609374922170066534400
%N A003805 Order of universal Chevalley group A_7 (q), q = prime power.
%D A003805 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 A003805 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 A003805 a(n) = A(A000961(n+1),7) where A(q,n) is defined in A003787. - _Sean A. Irvine_, Sep 18 2015
%t A003805 f[m_, n_] := m^(n (n + 1)/2) Product[m^k - 1, {k, 2, n + 1}]; f[#, 7] & /@ Select[Range[2, 8], PrimePowerQ] (* _Michael De Vlieger_, Sep 18 2015 *)
%K A003805 nonn,easy
%O A003805 1,1
%A A003805 _N. J. A. Sloane_
%E A003805 a(5)-a(6) from _Sean A. Irvine_, Sep 18 2015