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arXiv · 2210.09680

On function $SX$ of additive complements

Jin-Hui Fang·Csaba Sándor
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Abstract

Two sets $A,B$ of nonnegative integers are called \emph{additive complements}, if all sufficiently large integers can be expressed as the sum of two elements from $A$ and $B$. We further call $A,B$ \emph{perfect additive complements} if every nonnegative integer can be uniquely expressed as the sum of two elements from $A$ and $B$. Let $A(x)$ be the counting function of $A$. In this paper, we focus on the function $SX$, where $SX=\limsup_{x\rightarrow\infty}\frac{\max\{A(x),B(x)\}}{\sqrt{x}}$ was introduced by Erd\H{o}s and Freud in 1984. As a main result, we determine the value of $SX$ for perfect additive complements and further fix the infimum. We also give the absolute lower bound of $SX$ for additive complements.

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Jin-Hui Fang, Csaba Sándor. 2022-10-18. On function $SX$ of additive complements. https://arxiv.org/abs/2210.09680

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