Question: Error with Analytic()

Hi!

I am an error with the use of the function "Analytic" of the packpage RootFinding. These are the procedures:

CreaCos := proc (C, n, m, t) local k, F; F := C[1][1]+(C[1][2]-C[1][1])*t; for k to n-1 do F := F, C[k+1][1]+((1/2)*C[k+1][2]-(1/2)*C[k+1][1])*(1-cos(Pi*m^k*t)) end do; return F end proc;

Then, for k=50, 100, 150... the instruction

works correctly. However, for higher values of k (for instance, k=250) returns the below error. Some idea or suggets about occurs this error?

Many thanks for your time! 

Error, (in RootFinding:-Analytic) unable to evaluate `@`(evalf, proc (x) option remember; table( [( 0.524900000000000000000000000000e-1+Float(undefined)*I ) = Float(undefined)+Float(undefined)*I ] ) 31250*Pi*sin(62500*Pi*x)/(7/18-(1/2)*cos(62500*Pi*x)) end proc) at the value 0.524900000000000000000000000000e-1+Float(undefined)*I. The expression to be solved was probably not analytic.