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A126983 Expansion of 1/(1+x*c(x)), c(x) the g.f. of Catalan numbers A000108. 5
1, -1, 0, -1, -2, -6, -18, -57, -186, -622, -2120, -7338, -25724, -91144, -325878, -1174281, -4260282, -15548694, -57048048, -210295326, -778483932, -2892818244, -10786724388, -40347919626, -151355847012, -569274150156 (list; graph; refs; listen; history; internal format)
OFFSET

0,5

COMMENTS

Hankel transform is (-1)^n.

Catalan transform of A033999. [From R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Nov 11 2008]

FORMULA

a(n)=(-1)^n*A064310(n) . a(n)=Sum_{k, 0<=k<=n}A039599(n,k)*(-2)^k.

a(n)=Sum_{k, 0<=k<=n} A106566(n,k)*(-1)^k. a(0)=1, a(n)= -A000957(n) for n>0. [From Philippe DELEHAM (kolotoko(AT)wanadoo.fr), Nov 15 2009]

CROSSREFS

Sequence in context: A071721 A125306 A064310 * A104629 A000957 A125305

Adjacent sequences:  A126980 A126981 A126982 * A126984 A126985 A126986

KEYWORD

sign

AUTHOR

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

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Last modified February 15 13:57 EST 2012. Contains 205810 sequences.