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Erdős problem 251

Is ∑n=1∞pn2n\sum_{n=1}^\infty \frac{p_n}{2^n} irrational? Here pnp_n is the nn-th prime (p1=2,p2=3,…p_1=2, p_2=3, \dots).

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FormalConjectures/ErdosProblems/

251.lean

Retained formal statement1 of 1

Is ∑n=1∞pn2n\sum_{n=1}^\infty \frac{p_n}{2^n} irrational? Here pnp_n is the nn-th prime (p1=2,p2=3,…p_1=2, p_2=3, \dots).

FormalConjectures/ErdosProblems/251.leanErdos251.erdos_2511 lineExact file
True ↔ Irrational (∑' (n : ℕ), ↑(Nat.nth Nat.Prime n) / 2 ^ n)
OpenStatement only, no proof