Perhaps the most famous example of discrete "things" being solved by calculus is the Prime Number Theorem, and more generally all of analytic number theory, whi

Perhaps the most famous example of discrete "things" being solved by calculus is the Prime Number Theorem, and more generally all of analytic number theory, which uses calculus (and often complex numbers) to answer questions about the integers. https://en.wikipedia.org/wiki/Prime_number_theorem https://en.wikipedia.org/wiki/Prime_number_theorem https://en.wikipedia.org/wiki/Analytic_number_theory https://en.wikipedia.org/wiki/Analytic_number_theory