All Questions
1
question
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 ...