Hi, Im trying to illustrate a basic Taylor Series expansion example listed on document centre.
http://wolfram.com/xid/0gipeq-u3o Series[f[x], {x, a, 3}]
I obtain an answer with a function
(2^(-1-r) LerchPhi[(-1)^(1+r),1+r,1/2])+O[(2^(-1-r) LerchPhi[(-1)^(1+r),1+r,1/2])]^5
The correct answer should be f + f ' (x-a) + 0.5 f " (x-a)^2 +....
How can I correct the input command to receive the output interms of f , instead of Lerchphi.