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 A028675 #14 Jul 12 2025 08:32:14
%S A028675 1,156,4429152,21368939889024,17430690424387037091840,
%T A028675 2402962221899462961810522363863040,
%U A028675 55984406793280086114756507719510983331312762880,220431677762305366198023742325712037545142450383991425548943360
%N A028675 Galois numbers for p=13; order of group AGL(n,13).
%H A028675 Vincenzo Librandi, <a href="/A028675/b028675.txt">Table of n, a(n) for n = 0..29</a>
%H A028675 <a href="/index/Gre#groups">Index entries for sequences related to groups</a>.
%F A028675 a(n) = 13^n * Product_{k=0..n-1} (13^n - 13^k).
%F A028675 a(n) ~ c * 13^(n^2+n), where c = Product_{k>=1} (1 - 1/13^k) = 0.9171624725409... . - _Amiram Eldar_, Jul 12 2025
%t A028675 FoldList[ #1*13^#2 (13^#2-1)&, 1, Range[ 20 ] ]
%t A028675 a[n_] := 13^n * Product[13^n - 13^k, {k, 0, n-1}]; Array[a, 10, 0] (* _Amiram Eldar_, Jul 12 2025 *)
%o A028675 (PARI) a(n) = 13^n * prod(k = 0, n-1, 13^n - 13^k); \\ _Amiram Eldar_, Jul 12 2025
%Y A028675 Cf. A028365, A028665, A028667, A028669, A028673, A028679, A028681, A028685.
%K A028675 nonn
%O A028675 0,2
%A A028675 _Olivier Gérard_