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PutnamSuperchallengeIntegrals I: Feynman's Trick

Integrals I: Feynman's Trick · Superchallenge problem

A minimal-counterexample argument shows every integer n≥2n \ge 2 has a prime factor. Using the same idea, find the number of integers nn with 2≤n≤1002 \le n \le 100 whose smallest prime factor is greater than 77.