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A127053 Expansion of 1/(1+9*x*c(x)), where c(x) = g.f. for Catalan numbers A000108. +0
7
1, -9, 72, -585, 4734, -38358, 310662, -2516481, 20383110, -165104478, 1337341896, -10832484474, 87743071332, -710719065000, 5756823757890, -46630274845905, 377705217526470, -3059412293786310, 24781239462988800, -200728040080084110, 1625897123058144420 (list; graph; listen)
OFFSET

0,2

COMMENT

Hankel transform is (-9)^n.

FORMULA

a(n)=Sum_{k, 0<=k<=n}A039599(n,k)*(-10)^k.

MAPLE

c:=(1-sqrt(1-4*x))/2/x: ser:=series(1/(1+9*x*c), x=0, 24): seq(coeff(ser, x, n), n=0..21); - Emeric Deutsch (deutsch(AT)duke.poly.edu), Mar 23 2007

CROSSREFS

Sequence in context: A129328 A003951 A033135 this_sequence A001809 A006135 A133672

Adjacent sequences: A127050 A127051 A127052 this_sequence A127054 A127055 A127056

KEYWORD

sign

AUTHOR

Philippe DELEHAM (kolotoko(AT)wanadoo.fr), Mar 21 2007

EXTENSIONS

More terms from Emeric Deutsch (deutsch(AT)duke.poly.edu), Mar 23 2007

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Last modified July 25 07:41 EDT 2008. Contains 142293 sequences.


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