I took ToC about a year ago, as the final required course in my PhD studies, and we used Sipser’s text although the professor also wandered off into the arithme

I took ToC about a year ago, as the final required course in my PhD studies, and we used Sipser’s text although the professor also wandered off into the arithmetic hierarchy which he doesn’t cover. I will absolutely credit the course with igniting an intense curiosity in the foundations of computing (and of mathematics in general) but I agree that it’s time for a more modern approach.