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A127053 Expansion of 1/(1+9*x*c(x)), where c(x) = g.f. for Catalan numbers A000108. 6
1, -9, 72, -585, 4734, -38358, 310662, -2516481, 20383110, -165104478, 1337341896, -10832484474, 87743071332, -710719065000, 5756823757890, -46630274845905, 377705217526470, -3059412293786310, 24781239462988800, -200728040080084110, 1625897123058144420 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

Hankel transform is (-9)^n.

LINKS

Table of n, a(n) for n=0..20.

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, Mar 23 2007

CROSSREFS

Sequence in context: A003951 A252702 A033135 * A001809 A006135 A180836

Adjacent sequences:  A127050 A127051 A127052 * A127054 A127055 A127056

KEYWORD

sign

AUTHOR

Philippe Deléham, Mar 21 2007

EXTENSIONS

More terms from Emeric Deutsch, Mar 23 2007

STATUS

approved

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Last modified February 20 15:54 EST 2018. Contains 299380 sequences. (Running on oeis4.)