OFFSET
0,3
FORMULA
a(n) = binomial(2*n^2, n^2) / (n^2 + 1).
MATHEMATICA
CatalanNumber[Range[0, 10]^2] (* Harvey P. Dale, May 27 2013 *)
PROG
(PARI) {a(n)=binomial(2*n^2, n^2)/(n^2+1)}
for(n=0, 15, print1(a(n), ", "))
CROSSREFS
KEYWORD
nonn
AUTHOR
Paul D. Hanna, Jul 17 2012
STATUS
approved