login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A071731
Expansion of (1+x^3*C^2)*C^2, where C = (1-(1-4*x)^(1/2))/(2*x) is g.f. for Catalan numbers, A000108.
0
1, 2, 5, 15, 46, 146, 477, 1595, 5434, 18798, 65858, 233206, 833340, 3001316, 10883485, 39703635, 145612770, 536568150, 1985612310, 7376106210, 27495861060, 102820589820, 385609643250, 1449998633694, 5465731321476
OFFSET
0,2
CROSSREFS
Sequence in context: A139782 A378339 A047086 * A360272 A376574 A268648
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Jun 06 2002
STATUS
approved