0,3

Image of the Catalan numbers A000108 by the Riordan array (1,x(1-x^2)). Hankel transform is A006720(n+2).

Partial sums of A157002.

G.f.: c(x(1-x^2)) where c(x) is the g.f. of A000108;

a(n)=sum{k=0..n, (-1)^((n-k)/2)*(1+(-1)^(n-k))*C(k,floor((n-k)/2))*A000108(k)/2}.

Sequence in context: A002459 A104383 A108523 this_sequence A114507 A148105 A127386

Adjacent sequences: A157000 A157001 A157002 this_sequence A157004 A157005 A157006

easy,nonn

Paul Barry (pbarry(AT)wit.ie), Feb 20 2009