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 A028668 #14 Jul 14 2025 00:25:37
%S A028668 1,30,37800,1755432000,2946176634240000,178121125423535616000000,
%T A028668 387722609071165087097978880000000,
%U A028668 30383449623465746081582327522446540800000000,85714999722921366207156144059911618537426255872000000000,8705210793883473550569112250184122162504600827770940780707840000000000
%N A028668 Pseudo Galois numbers for d=6.
%H A028668 Vincenzo Librandi, <a href="/A028668/b028668.txt">Table of n, a(n) for n = 0..35</a>
%F A028668 a(n) = 6^n * Product_{k=0..n-1} (6^n - 6^k).
%F A028668 a(n) ~ c * 6^(n^2+n), where c = A132034. - _Amiram Eldar_, Jul 13 2025
%t A028668 FoldList[ #1*6^#2 (6^#2-1)&, 1, Range[ 20 ] ]
%t A028668 a[n_] := 6^n * Product[6^n - 6^k, {k, 0, n-1}]; Array[a, 10, 0] (* _Amiram Eldar_, Jul 13 2025 *)
%o A028668 (PARI) a(n) = 6^n * prod(k = 0, n-1, 6^n - 6^k); \\ _Amiram Eldar_, Jul 13 2025
%Y A028668 Cf. A028670, A028671, A028672, A028674, A028676, A028677, A028678, A028680, A028682, A028683, A028684, A028686.
%Y A028668 Cf. A132034.
%K A028668 nonn
%O A028668 0,2
%A A028668 _Olivier Gérard_