OFFSET
0,3
MAPLE
with(numtheory):with(combinat):a:=n->phi(binomial(2*n, n)*n): seq(a(n), n=0..25);
MATHEMATICA
Table[EulerPhi[Binomial[2n, n]n], {n, 0, 30}] (* Harvey P. Dale, Apr 15 2012 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Zerinvary Lajos, Oct 05 2007
STATUS
approved