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A117259 Column 0 of triangle A117258. 1
1, 1, -2, 32, -2560, 917504, -1409286144, 9070970929152, -241505530017742848, 26378844025404658810880, -11755594669932654094842855424, 21291459481433341027538627037495296, -156279993920424129009046403691280672489472 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

Table of n, a(n) for n=0..12.

FORMULA

a(n) = [prod_{j=0..n-1} (1-2*j)]/n! * 4^(n*(n-1)/2).

PROG

(PARI) {a(n)=local(m=1, p=2, q=4, r=1); prod(j=0, n-1, m*r-p*j)/n!*q^(n*(n-1)/2)}

CROSSREFS

Sequence in context: A193269 A088386 A093584 * A234365 A068183 A166077

Adjacent sequences:  A117256 A117257 A117258 * A117260 A117261 A117262

KEYWORD

sign

AUTHOR

Paul D. Hanna, Mar 14 2006

STATUS

approved

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Last modified April 23 13:21 EDT 2014. Contains 240928 sequences.