@xurxia
I don't know your level of understanding of math, so I'll put here 2 links, one with a more generalist explanation,

https://gereshes.com/2018/05/07/what-is-the-n-body-problem/

and other a little more math/solution oriented,

https://legacy-www.math.harvard.edu/archive/118r_spring_05/handouts/nbody.pdf

I hope one of them may be of some interest to you.