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Erdős problem 69

Is ∑n≥2ω(n)2n \sum_{n\geq 2}\frac{\omega(n)}{2^n} irrational? (Here ω(n)\omega(n) counts the number of distinct prime divisors of nn.)

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2 retained statements36c6d0fef71a

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FormalConjectures/ErdosProblems/

69.lean

Retained formal statement1 of 2

Is ∑n≥2ω(n)2n \sum_{n\geq 2}\frac{\omega(n)}{2^n} irrational? (Here ω(n)\omega(n) counts the number of distinct prime divisors of nn.)

FormalConjectures/ErdosProblems/69.leanErdos69.erdos_691 lineExact file
Irrational (∑' (n : ℕ), ↑(ArithmeticFunction.cardDistinctFactors (n + 2)) / 2 ^ (n + 2))
TextbookStatement only, no proof