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Problem #31: Given any infinite set $A\subset \mathbb{N}$ there is a set...

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.

Problem Statement

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.
Categories: Number Theory Additive Basis

Progress

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

Source: erdosproblems.com/31 | Last verified: January 13, 2026

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