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 A003854 #21 Jun 24 2025 11:03:07
%S A003854 911666827031785075278550369566720000,
%T A003854 393736985584514548835738283681336315795223487793070080000,
%U A003854 1649493899207759406688161287839326786813727965837588934265143296000000000
%N A003854 Order of simple Chevalley group D_8(q), q = prime power.
%D A003854 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 A003854 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 A003854 Sean A. Irvine, <a href="/A003854/b003854.txt">Table of n, a(n) for n = 1..10</a>
%H A003854 <a href="/index/Gre#groups">Index entries for sequences related to groups</a>.
%F A003854 a(n) = d(A000961(n+1),8) where d(q,n) is defined in A003837. - _Sean A. Irvine_, Sep 17 2015
%t A003854 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, 8], {q, Select[Range[10], PrimePowerQ]}] (* _Amiram Eldar_, Jun 24 2025 *)
%Y A003854 Cf. A000961, A003808, A003837, A003848, A003850, A003851, A003852, A003853.
%K A003854 nonn,easy
%O A003854 1,1
%A A003854 _N. J. A. Sloane_
%E A003854 More terms from _Sean A. Irvine_, Sep 17 2015