Let y=(1-sqrt(1-4*z))/(1+sqrt(1-4*z)) denote the g.f. for the Catalan numbers (A000108); sequence has g.f. sum(k>=1, y^(2^k)/(1+y^(2^(k+1))) ).

A191606

Let y=(1-sqrt(1-4*z))/(1+sqrt(1-4*z)) denote the g.f. for the Catalan numbers (A000108); sequence has g.f. sum(k>=1, y^(2^k)/(1+y^(2^(k+1))) ).