Erdős Problem #31

Given any infinite set $A\subset \mathbb{N}$ there is a set $B$ of density $0$ such that $A+B$ contains all except finitely many integers.

#31: [Er56][Er59][Er65b][Er73]

number theory | additive basis

Conjectured by Erdős and Straus. Proved by Lorentz [Lo54].

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