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Erdős problem 348

For what values of 0≤m<n0 \leq m < n is there a complete sequence A={a1≤a2≤⋯ }A = \{a_1 \leq a_2 \leq \cdots\} of integers such that 1. AA remains complete after removing any mm elements, but 2. AA is not complete after removing any nn elements.

Sources

The source's own material, retained exactly.

1 retained statement36c6d0fef71a

Open selected source

FormalConjectures/ErdosProblems/

348.lean

Retained formal statement1 of 1

For what values of 0≤m<n0 \leq m < n is there a complete sequence A={a1≤a2≤⋯ }A = \{a_1 \leq a_2 \leq \cdots\} of integers such that 1. AA remains complete after removing any mm elements, but 2. AA is not complete after removing any nn elements.

FormalConjectures/ErdosProblems/348.leanErdos348.erdos_3488 linesExact file
{x |    ∃ m n,      ∃ (_ : m < n),        ∃ a,          ∃ (_ : Monotone a) (_ :            ∀ (s : Finset ℕ), s.card = m → IsAddComplete (Set.range (Function.updateFinset a s 0))) (_ :            ∀ (t : Finset ℕ), t.card = n → ¬IsAddComplete (Set.range (Function.updateFinset a t 0))), (m, n) = x} =  sorry
OpenStatement only, no proof