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3 votes
3 answers
386 views

$\operatorname{Li}_{2} \left(\frac{1}{e^{\pi}} \right)$ as a limit of a sum

Working on the same lines as This/This and This I got the following expression for the Dilogarithm $\operatorname{Li}_{2} \left(\frac{1}{e^{\pi}} \right)$: $$\operatorname{Li}_{2} \left(\frac{1}{e^{\...
Srini's user avatar
  • 862
0 votes
0 answers
96 views

$\operatorname{Li}_{2} \left(\frac12 \right)$ vs $\operatorname{Li}_{2} \left(-\frac12 \right)$ : some long summation expressions

Throughout this post, $\operatorname{Li}_{2}(x)$ refers to Dilogarithm. While playing with some Fourier Transforms, I came up with the following expressions: $$2 \operatorname{Li}_{2}\left(\frac12 \...
Srini's user avatar
  • 862
0 votes
1 answer
99 views

Converting a 2D lattice sum into a sum over 1D lattice sums in a circle

I'm working on a physics problem. I have a lattice sum, which in 1D is a sum over a linear chain. It reads $$ f_k = \sum_{n=1}^\infty \frac{2\cos(kn)}{n^3}. $$ This can be written in terms of ...
Tom's user avatar
  • 510
2 votes
0 answers
75 views

The summation $\sum_{k=1}^{\infty} \frac{\phi^{-2k}}{k^2}=\text{Li}_2(1/\phi^2)=\frac{\pi^2}{15}-\ln^2 \phi$ [duplicate]

In a recent post Computing $\int_0^{1/2}\frac{\sinh^{-1}(u)}{u} \,du=\frac{\pi^2}{20}$, $\zeta(2)=\frac53 \sum_{n=0}^\infty \frac{(-1)^n\binom{2n}{n}}{2^{4n}(2n+1)^2}$ I evaluated the required ...
Z Ahmed's user avatar
  • 43.6k
1 vote
1 answer
59 views

Further Stirling number series resummation

\begin{equation} \sum_{m=1}^\infty\sum_{n=1}^\infty (-1)^{n } \frac{S_m^{(3)}}{m! n}(-1 + u)^{(m + n - 1)} (\frac{x}{-1 + x})^m \end{equation} Note: $S^{(3)}_m$ belongs to the Stirling number of the ...
YU MU's user avatar
  • 99
0 votes
0 answers
59 views

Stirling number series resummation

\begin{equation}\sum_{m=1}^{\infty}\frac{a_1^3 S_m^{(3)} (u-1)^{m-1} \left(\frac{x}{x-1}\right)^m}{m!}\end{equation} Does somebody know the result of this resummation? Note: $S_m^{(3)} $ belongs to ...
YU MU's user avatar
  • 99
0 votes
0 answers
82 views

General expression of a triangle sequence

\begin{gather*} \frac{1}{4} \\ \frac{1}{4} \quad \frac{1}{4} \\ \frac{11}{48} \quad \frac{1}{4} \quad \frac{11}{48} \\ \frac{5}{24} \quad \frac{11}{48} \quad \frac{11}{48} \quad \frac{5}{24} \\ \frac{...
YU MU's user avatar
  • 99