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A216788
a(n) = Product_{k=1..n} (169 - 13/k).
0
1, 156, 25350, 4174300, 691890225, 115130533440, 19207610662240, 3210414924974400, 537343198067590200, 90034838076214002400, 15098842345381088202480, 2533860269961226256525280, 425477370330989242241536600, 71480198215606192696578148800
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).
MAPLE
seq(product(169-13/k, k=1.. n), n=0..20);
seq((13^n/n!)*product(13*k+12, k=0.. n-1), n=0..20);
MATHEMATICA
Table[Product[169-13/k, {k, n}], {n, 0, 20}] (* Harvey P. Dale, Mar 13 2013 *)
KEYWORD
nonn
AUTHOR
Michel Lagneau, Sep 16 2012
STATUS
approved