A117257 Column 0 of triangle A117256.

1, 1, -10, 750, -328125, 779296875, -9741210937500, 630569458007812500, -209368765354156494140625, 354400253854691982269287109375, -3045627181563759222626686096191406250, 132489108572997338342247530817985534667968750

Offset

0,3

Links

Table of n, a(n) for n=0..11.

Formula

a(n) = [prod_{j=0..n-1} (1-5*j)]/n! * 5^(n*(n-1)/2).

Prog

(PARI) {a(n)=local(m=1, p=5, q=5, r=1); prod(j=0, n-1, m*r-p*j)/n!*q^(n*(n-1)/2)}

Crossrefs

Sequence in context: A053468 A008272 A015509 * A030979 A183288 A108247

Adjacent sequences: A117254 A117255 A117256 * A117258 A117259 A117260

Keyword

sign

Author

Paul D. Hanna, Mar 14 2006

Status

approved