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If $A$ is an additive basis order $2$, and $1_A\ast 1_A(n)\to \infty$ as $n\to \infty$, then must $A$ contain a minimal additive basis of order $2$? (i.e. such that deleting any element creates infinitely many $n\not\in A+A$)

What if $1_A\ast 1_A(n) >\epsilon \log n$ (for all large $n$, for arbitrary fixed $\epsilon>0$)?

A question of Erdős and Nathanson [ErNa79], who proved that this is true if $1_A\ast 1_A(n) > (\log \frac{4}{3})^{-1}\log n$ for all large $n$.

Härtter [Ha56] and Nathanson [Na74] proved that there exist additive bases which do not contain any minimal additive bases.

See also [870].