I am in kind of a dilemma(ish) situation. I am a rising junior, and I plan on applying to graduate school in math, but I have not shut the door on graduate programs in CS or applied math either (am interested in algorithms, combinatorics, optimization, etc.).
There is one professor at my school who I am pretty close with in the CS department, who I also plan on doing research with. This professor does research in algorithmic game theory, which for all intents and purposes (at least in my opinion) is hopefully pretty close to "math".
I think they would be able to write a good recommendation letter, and it certainly would be helpful if I decided to apply to CS graduate school. However, would math graduate admissions prefer such a letter over a teacher I had? I would presume so, but I just wanted to make sure.
Also, on the flip side, would a recommendation from a professor in math help for CS? The professor in mind mostly does combinatorics. Thanks for your help!