A028665 Galois numbers for p=3; order of group AGL(n,3).

1, 6, 432, 303264, 1965150720, 115562653240320, 61330486826476707840, 293207687471256968260730880, 12619705781992895315056778792140800, 4888884191426907931326620039839052385484800, 17046196453240220939126401085378073952125928970649600

Offset

0,2

Links

Vincenzo Librandi, Table of n, a(n) for n = 0..45

Index entries for sequences related to groups.

Formula

a(n) = 3^n * Product_{k=0..n-1} (3^n - 3^k).

a(n) ~ c * 3^(n^2+n), where c = A100220. - Amiram Eldar, Jul 12 2025

Mathematica

FoldList[ #1*3^#2 (3^#2-1)&, 1, Range[ 20 ]]
a[n_] := 3^n * Product[3^n - 3^k, {k, 0, n-1}]; Array[a, 11, 0] (* Amiram Eldar, Jul 12 2025 *)

Prog

(PARI) a(n) = 3^n * prod(k = 0, n-1, 3^n - 3^k); \\ Amiram Eldar, Jul 12 2025

Crossrefs

Cf. A028365, A028667, A028669, A028673, A028675, A028679, A028681, A028685.

Cf. A100220.

Sequence in context: A269882 A262013 A379913 * A231316 A393843 A270066

Adjacent sequences: A028662 A028663 A028664 * A028666 A028667 A028668

Keyword

nonn

Author

Olivier Gérard

Status

approved