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A114190 Expansion of 1/(1+x(1-x)c(-2x)), c(x) the g.f. of A000108. 1
1, -1, 4, -17, 87, -490, 2945, -18517, 120340, -802005, 5451651, -37652546, 263480357, -1864065017, 13311094644, -95816113129, 694511157535, -5064818563258, 37135165923801, -273581694291309, 2024194855052180, -15034769479254861, 112062948489702251, -837936593024505298 (list; graph; refs; listen; history; internal format)
OFFSET

0,3

COMMENTS

Diagonal sums of A114189. Alernating sign version of A110508.

FORMULA

G.f.: 4/(3+x+(1-x)sqrt(1+8x)).

Conjecture: n*a(n) +(7n-10)*a(n-1) +2*(14-3n)*a(n-2) +(13n-20)*a(n-3) +(66-23n)*a(n-4) +4*(2n-7)*a(n-5)=0. - R. J. Mathar, Dec 10 2011

CROSSREFS

Sequence in context: A163071 A056542 A110508 * A135168 A058279 A143405

Adjacent sequences:  A114187 A114188 A114189 * A114191 A114192 A114193

KEYWORD

easy,sign

AUTHOR

Paul Barry (pbarry(AT)wit.ie), Nov 16 2005

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Last modified February 17 00:09 EST 2012. Contains 205978 sequences.