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 A028667 #15 Jul 12 2025 08:34:03
%S A028667 1,20,12000,186000000,72540000000000,708171750000000000000,
%T A028667 172882428468750000000000000000,
%U A028667 1055177097007236328125000000000000000000,161006835289591673217773437500000000000000000000000,614192019859664935862872123718261718750000000000000000000000000
%N A028667 Galois numbers for p=5; order of group AGL(n,5).
%H A028667 Vincenzo Librandi, <a href="/A028667/b028667.txt">Table of n, a(n) for n = 0..37</a>
%H A028667 <a href="/index/Gre#groups">Index entries for sequences related to groups</a>.
%F A028667 a(n) = 5^n * Product_{k=0..n-1} (5^n - 5^k).
%F A028667 a(n) ~ c * 5^(n^2+n), where c = A100222. - _Amiram Eldar_, Jul 12 2025
%t A028667 FoldList[ #1*5^#2 (5^#2-1)&, 1, Range[ 20 ] ]
%t A028667 a[n_] := 5^n * Product[5^n - 5^k, {k, 0, n-1}]; Array[a, 10, 0] (* _Amiram Eldar_, Jul 12 2025 *)
%o A028667 (PARI) a(n) = 5^n * prod(k = 0, n-1, 5^n - 5^k); \\ _Amiram Eldar_, Jul 12 2025
%Y A028667 Cf. A028365, A028665, A028669, A028673, A028675, A028679, A028681, A028685.
%Y A028667 Cf. A100222.
%K A028667 nonn
%O A028667 0,2
%A A028667 _Olivier Gérard_