I have the following expression that I need to series expand, around t=0
(PolyLog[3, 1 + Tanh[J t]] - PolyLog[3, 1 - Tanh[J t]])Tanh[J t]
The amount of time to calculate one extra term is kind of just blowing up exponentially. I need at least 30 terms but for 20 terms only my time exceeded more than 30mins. To further speed up the process, I tried to use
Assumptions command, with t>0, but it didn't help either. Infact I further tried to simply and do the series expansion of following expression around t=0
(PolyLog[3, 1 + t] - PolyLog[3, 1 - t])
and found that it is time taking too. I want to know if it is possible to simplify somehow the expression that I have in order to speed up the process? Or if there is some other way to find the Series expansion faster and efficiently?
Edit: I found with a little bit of experimentation that, the expansion of the Polylog is fast. In case instead of
PolyLog[3, 1 + Tanh[J t]] if I had
PolyLog[3, Tanh[J t]] then the series expansion around t=0 is pretty quick even up to 50 terms.