login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A216704
a(n) = Product_{k=1..n} (64 - 8/k).
7
1, 56, 3360, 206080, 12776960, 797282304, 49963024384, 3140532961280, 197853576560640, 12486759054049280, 789163172215914496, 49932506169297862656, 3162392057388864634880, 200447004252955727626240, 12714067126901763295150080, 806919460320698577132191744
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
MAPLE
seq(product(64-8/k, k=1.. n), n=0..20);
seq((8^n/n!)*product(8*k+7, k=0.. n-1), n=0..20);
MATHEMATICA
Table[Product[64-8/k, {k, n}], {n, 0, 20}] (* Harvey P. Dale, Sep 23 2017 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Michel Lagneau, Sep 16 2012
STATUS
approved