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 A003850 #17 Jun 24 2025 11:03:25
%S A003850 174182400,4952179814400,67010895544320000,8911539000000000000,
%T A003850 112554991177798901760000,19031213036231093492121600,
%U A003850 129182006871144805294080000,35749625435272978955066880000
%N A003850 Order of simple Chevalley group D_4(q), q = prime power.
%D A003850 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 A003850 H. S. M. Coxeter and W. O. J. Moser, Generators and Relations for Discrete Groups, 4th ed., Springer-Verlag, NY, reprinted 1984, p. 131.
%H A003850 <a href="/index/Gre#groups">Index entries for sequences related to groups</a>.
%F A003850 a(n) = d(A000961(n+1),4) where d(q,n) is defined in A003837. - _Sean A. Irvine_, Sep 17 2015
%t A003850 d[q_, n_] := q^(n*(n-1)) * (q^n-1) * Product[q^(2*k) - 1, {k, 1, n-1}] / GCD[4, q^n-1]; Table[d[q, 4], {q, Select[Range[20], PrimePowerQ]}] (* _Amiram Eldar_, Jun 24 2025 *)
%Y A003850 Cf. A000961, A003808, A003837, A003848, A003851, A003852, A003853, A003854.
%K A003850 nonn,easy
%O A003850 1,1
%A A003850 _N. J. A. Sloane_