>>11043323I don't know how advanced your mathematical knowledge is, but look into "combinatorics on words". It's super comfy desu, has a fuckton of applications and can be learned with fairly little mathematical knowledge - abstract algebra, basic combinatorics, and basic formal logic. And actually, even you didn't know much about these subject you'll at least be able to get something out of the basics.
>>11042087Applied math and/or discrete math is your best bet. Lately I've been learning the basics of game theory and social choice theory, so thats the first thing that comes to my mind.