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import FormalConjecturesUtilErdős Problem 109
[MRR19] J. Moreira, F.K. Richter, and D. Robertson, A proof of a sumset conjecture of Erdős, Annals of Math. 189 (2019), 605-652.
open Pointwise
namespace Erdos109
Any $A\subseteq \mathbb{N}$ of positive upper density contains a sumset $B+C$ where both $B$ and $C$ are infinite.
The Erdős sumset conjecture. Proved by Moreira, Richter, and Robertson [MRR19].
@[category research solved, AMS 5]
theorem erdos_109 (A : Set ℕ) (h : A.upperDensity > 0) :
∃ B C : Set ℕ, B.Infinite ∧ C.Infinite ∧ B + C ⊆ A := A:Set ℕh:A.upperDensity > 0⊢ ∃ B C, B.Infinite ∧ C.Infinite ∧ B + C ⊆ A
All goals completed! 🐙
end Erdos109