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A126985 Expansion of 1/(1+8*x*c(x)), c(x) the g.f. of Catalan numbers A000108. 5
1, -8, 56, -400, 2840, -20208, 143664, -1021728, 7265240, -51665200, 367392656, -2612584928, 18578329456, -132112749920, 939467783520, -6680662171200, 47506922377560, -337827035002800, 2402325467002320, -17083203745473120, 121480558396908240, -863861754435010080 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

Hankel transform is (-8)^n.

Catalan transform of (-1)^n*A001018(n). [From R. J. Mathar, Nov 11 2008]

LINKS

Table of n, a(n) for n=0..21.

FORMULA

a(n)=Sum_{k, 0<=k<=n}A039599(n,k)*(-9)^k.

MAPLE

c:=(1-sqrt(1-4*x))/2/x: ser:=series(1/(1+8*x*c), x=0, 25): seq(coeff(ser, x, n), n=0..21); - Emeric Deutsch, Mar 24 2007

CROSSREFS

Sequence in context: A003950 A252701 A033134 * A182430 A027081 A093134

Adjacent sequences:  A126982 A126983 A126984 * A126986 A126987 A126988

KEYWORD

sign

AUTHOR

Philippe Deléham, Mar 21 2007

EXTENSIONS

More terms from Emeric Deutsch, Mar 24 2007

STATUS

approved

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Last modified October 16 19:22 EDT 2018. Contains 316271 sequences. (Running on oeis4.)