OFFSET
0,2
COMMENTS
The next term has 150 digits. - Harvey P. Dale, Jan 09 2017
FORMULA
a(n) = C(2^(n+2)-4, 2^(n+1)-2) / (2^(n+1)-1).
MATHEMATICA
Table[Binomial[2^(n + 2) - 4, 2^(n + 1) - 2]/(2^(n + 1) - 1), {n, 0, 10}] (* G. C. Greubel, Nov 07 2016 *)
Table[SelectFirst[CatalanNumber[Range[300]], Divisible[#, 2^n]&], {n, 0, 7}] (* Harvey P. Dale, Jan 09 2017 *)
PROG
(PARI) {a(n) = binomial(2^(n+2)-4, 2^(n+1)-2) / (2^(n+1)-1)}
for(n=0, 8, print1(a(n), ", "))
CROSSREFS
KEYWORD
nonn
AUTHOR
Paul D. Hanna, Dec 02 2007
STATUS
approved