OFFSET
1,2
COMMENTS
There is at least one published paper that refers to binomial(2n,n)/(2n) as the Catalan numbers. Of course the Catalan numbers are really A000108.
LINKS
Patrick Dehornoy, On the rotation distance between binary trees, Adv. Math. 223 (2010), no. 4, 1316-1355.
EXAMPLE
1, 3/2, 10/3, 35/4, 126/5, 77, 1716/7, 6435/8, 24310/9, 46189/5, 352716/11, 676039/6, ...
MATHEMATICA
Numerator[Table[Binomial[2n, n]/(2n), {n, 30}]] (* Harvey P. Dale, Jan 06 2013 *)
CROSSREFS
KEYWORD
nonn,frac
AUTHOR
N. J. A. Sloane, Nov 26 2011
STATUS
approved