OFFSET
0,2
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 0..32
FORMULA
a(n) = 9^n * Product_{k=0..n-1} (9^n - 9^k).
a(n) ~ c * 9^(n^2+n), where c = A132037. - Amiram Eldar, Jul 13 2025
MATHEMATICA
FoldList[ #1*9^#2 (9^#2-1)&, 1, Range[ 20 ] ]
a[n_] := 9^n * Product[9^n - 9^k, {k, 0, n-1}]; Array[a, 9, 0] (* Amiram Eldar, Jul 13 2025 *)
PROG
(PARI) a(n) = 9^n * prod(k = 0, n-1, 9^n - 9^k); \\ Amiram Eldar, Jul 13 2025
CROSSREFS
KEYWORD
nonn
AUTHOR
STATUS
approved
