A216788 a(n) = Product_{k=1..n} (169 - 13/k).

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).

Links

Table of n, a(n) for n=0..13.

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 *)

Crossrefs

Cf. A004988, A049382, A004994, A216702, A216703, A216704, A216705, A216706, A216786, A216787.

Sequence in context: A252778 A006112 A239410 * A239338 A028675 A248504

Adjacent sequences: A216785 A216786 A216787 * A216789 A216790 A216791

Keyword

nonn

Author

Michel Lagneau, Sep 16 2012

Status

approved