taylor expansion with arbritary precision numbers

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Hi,

if I define a function with arbritary precision numbers (e.g., f=0.123456789123456789*log(1+x)) and then compute its Taylor expansion (f.taylor(x,0,5)) it seems to me that the coefficients are given in double precision, whereas if I compute them (e.g., by derivative(f,x,5)(x=0)/factorial(5)) they are in original precision. First of all, am I right or is it only a visualisation difference? If I'm right, is it possible to compute the Taylor expansion with the original precision?

Cheers,

Marco