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Source. Lemma 2, printed p. 87 (PDF p. 3).
Statement. The number of positive integers divisible by for some prime is .
Full proof
The number is at most
For large , split the primes above into intervals , . The prime number theorem implies the uniform upper estimate for all sufficiently large . Thus
Taking gives , as required. No independence of prime divisibility events is assumed.
Use. Lemma 3 can therefore take every prime factor exceeding with exponent one, after deleting the stated exceptional set.
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