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Erdős problem 229

Let (Sn)n≥1(S_n)_{n \ge 1} be a sequence of sets of complex numbers, none of which have a finite limit point. Does there exist an entire transcendental function f(z)f(z) such that, for all n≥1n \ge 1, there exists some kn≥0k_n \ge 0 such that f(kn)(z)=0f^{(k_n)}(z) = 0 for all z∈Snz \in S_n.

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2 retained statements36c6d0fef71a

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FormalConjectures/ErdosProblems/

229.lean

Retained formal statement2 of 2

Let {Sk}\{S_k\} be any sequence of sets in the complex plane, each of which has no finite limit point. Then there exists a sequence {nk}\{n_k\} of positive integers and a transcendental entire function f(z)f(z) such that f(nk)(z)=0f^{(n_k)}(z) = 0 if z∈Skz \in S_k.

FormalConjectures/ErdosProblems/229.leanErdos229.theorem_15 linesExact file
∀ {S : ℕ → Set ℂ},  (∀ (k : ℕ), derivedSet (S k) = ∅) →    ∃ f n,      Differentiable ℂ f ∧        Transcendental (Polynomial ℂ) f ∧ ∀ (k : ℕ), 0 < n k ∧ ∀ {z : ℂ}, z ∈ S k → iteratedDeriv (n k) f z = 0
SolvedStatement only, no proof