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Erdős problem 830

We say that a,bNa,b\in \mathbb{N} are an amicable pair if σ(a)=σ(b)=a+b\sigma(a)=\sigma(b)=a+b. If A(x)A(x) counts the number of amicable 1abx1\leq a\leq b\leq x then one can show that A(x)xexp((12+o(1))(logxloglogx)1/2)A(x) \leq x \exp(-(\tfrac{1}{2}+o(1))(\log x\log\log x)^{1/2}).

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830.lean

Retained formal statement2 of 5

Erdos Problem 830, Part 2 We say that a,bNa,b\in \mathbb{N} are an amicable pair if σ(a)=σ(b)=a+b\sigma(a)=\sigma(b)=a+b. If A(x)A(x) counts the number of amicable 1abx1\leq a\leq b\leq x then is it true that A(x)>x1o(1)?A(x) > x^{1-o(1)}?

FormalConjectures/ErdosProblems/830.leanErdos830.erdos_830.parts.ii1 lineExact file
sorry ↔ ∃ o, o =o[Filter.atTop] 1 ∧ ∀ᶠ (x : ℝ) in Filter.atTop, x ^ (1 - o x) < Erdos830.A x
OpenStatement only, no proof

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