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Erdős problem 357

Let f(n)f(n) be the maximal kk such that there exist integers 1≤a1<…<ak≤n1 \le a_1 < \dotsc < a_k \le n such that all sums of the shape ∑u≤i≤vai\sum_{u \le i \le v} a_i are distinct. It is known that f(n)≥(2+o(1))nf(n) \geq (2+o(1))\sqrt{n}. Source: See comment by Desmond Weisenberg here: https://www.erdosproblems.com/forum/thread/357.

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17 retained statements36c6d0fef71a

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FormalConjectures/ErdosProblems/

357.lean

Retained formal statement7 of 17

Let g(n)g(n) be the maximal kk such that there exist integers 1≤a1,…,ak≤n1 \le a_1, \dotsc, a_k \le n such that all sums of the shape ∑u≤i≤vai\sum_{u \le i \le v} a_i are distinct. It is known that (13+o(1))n≤g(n)≤(23+o(1))n.\left(\frac 1 3 + o(1) \right)n \leq g(n) \leq \left(\frac 2 3 + o(1) \right)n.

FormalConjectures/ErdosProblems/357.leanErdos357.erdos_357.variants.hegyvari4 linesExact file
∃ o o',  o =o[Filter.atTop] 1 ∧    o' =o[Filter.atTop] 1 ∧      ∀ᶠ (n : ℕ) in Filter.atTop, ↑(Erdos357.g n) ∈ Set.Icc ((1 / 3 + o n) * ↑n) ((2 / 3 + o' n) * ↑n)
OpenStatement only, no proof