I find series even more fascinating than unexpected constants. Series also show up in the weirdest places and it's often very non-trivial to explain (or not yet

I find series even more fascinating than unexpected constants. Series also show up in the weirdest places and it's often very non-trivial to explain (or not yet explained at all) why the some series shows up in two different areas/applications. Check out the comments in OEIS[1] entries, it's fascinating. [1] https://oeis.org https://oeis.org