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Erdős problem 677

Denote by M(n,k)M(n, k) the least common multiple of the finite set {n+1,…,n+k}\{n+1, \dotsc, n+k\}. Is it true that for all m≥n+km \geq n + k, we get M(m,k)≠M(n,k)M(m, k) \neq M(n, k)?

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The source's own material, retained exactly.

2 retained statements36c6d0fef71a

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FormalConjectures/ErdosProblems/

677.lean

Retained formal statement2 of 2

Erdős expected very few solutions for M(n,k)=M(m,l)M(n, k) = M(m, l), where m≥n+km \geq n + k and l>1l > 1. The only solutions he knew were the following.

FormalConjectures/ErdosProblems/677.leanErdos677.lcmInterval_eq_example11 lineExact file
Finset.lcmInterval 4 3 = Finset.lcmInterval 13 2 ∧ Finset.lcmInterval 3 4 = Finset.lcmInterval 19 2
TestStatement only, no proof