OFFSET
0,2
COMMENTS
This sequence is generalizable: Product_{k=1..n} (q^2 - q/k) = (q^n/n!) * Product_{k=0..n-1} (q*k + q-1) = expansion of (1- x*q^2)^((1-q)/q).
LINKS
Harvey P. Dale, Table of n, a(n) for n = 0..524
MAPLE
seq(product(81-9/k, k=1.. n), n=0..20);
seq((9^n/n!)*product(9*k+8, k=0.. n-1), n=0..20);
MATHEMATICA
Table[Product[81-9/k, {k, n}], {n, 0, 20}] (* Harvey P. Dale, Jul 20 2021 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Michel Lagneau, Sep 16 2012
STATUS
approved