A028685 Galois numbers for p=23; order of group AGL(n,23).

1, 506, 141331872, 20920469730667584, 1638296742744745305180456960, 67868907839960050279986415163868117749760, 1487321615877089920298398794877451264100990832314711736320

Offset: 0

Author

Olivier Gérard

Keywords

• nonn

Links

• Vincenzo Librandi, Table of n, a(n) for n = 0..26
• Index entries for sequences related to groups.

Crossrefs

Cf. A028365, A028665, A028667, A028669, A028673, A028675, A028679, A028681.

Programs

Mathematica

FoldList[ #1*23^#2 (23^#2-1)&, 1, Range[ 20 ] ]
a[n_] := 23^n * Product[23^n - 23^k, {k, 0, n-1}]; Array[a, 7, 0] (* Amiram Eldar, Jul 12 2025 *)

PARI

a(n) = 23^n * prod(k = 0, n-1, 23^n - 23^k); \\ Amiram Eldar, Jul 12 2025

Formula

a(n) = 23^n * Product_{k=0..n-1} (23^n - 23^k).

a(n) ~ c * 23^(n^2+n), where c = Product_{k>=1} (1 - 1/23^k) = 0.954631535623... . - Amiram Eldar, Jul 12 2025