Remarks on Pinasco's Proof of the Infinitude of Primes

In this section of Resonance, we invite readers to pose questions likely to be raised in a classroom situation. We may suggest strategies for dealing with them, or invite responses, or both. "Classroom" is equally a forum for raising broader issues and sharing personal experiences and viewpoints on matters related to teaching and learning science. Using Mobius inversion formula, we give a concise elementary proof of the formula due to J. P. Pinasco in 2009, which was applied in his proof of Euclid's theorem on the infinitude of primes. Consequently, using a simpler argument than those of Pinasco's proof, we prove the infinitude of primes.