1398696domain: NAppears in sequencesTriangle T(n,m), [x*A(x)]^m=sum(n>=m T(n,m)*x^n), where A(x) satisfies x*A(x)^2= -(2*x*A(x)+sqrt(1-4*x*A(x))-1)/(4*x*A(x)+sqrt(1-4*x*A(x))-1).at n=28A188109G.f. A(x) satisfies: A(x) = 1/(1 - 2*x*A(x) - x*A(x)/(1 - x*A(x)/(1 - x*A(x)/(1 - ...)))), a continued fraction.at n=7A307489