English

On the integer sets with the same representation functions

Number Theory 2021-11-16 v1

Abstract

Let N\mathbb{N} be the set of all nonnegative integers. For SNS\subseteq \mathbb{N} and nNn\in \mathbb{N}, let RS(n)R_S(n) denote the number of solutions of the equation n=s1+s2n=s_1+s_2, s1,s2Ss_1,s_2\in S and s1<s2s_1<s_2. Let AA be the set of all nonnegative integers which contain an even number of digits 11 in their binary representations and B=NAB=\mathbb{N}\setminus A. Put Al=A[0,2l1]A_l=A\cap [0,2^l-1] and Bl=B[0,2l1]B_l=B\cap [0,2^l-1]. In 2017, Kiss and S\'{a}ndor proved that, if CD=[0,m]C\cup D=[0,m], 0C0\in C and CD={r}C\cap D=\{r\}, then RC(n)=RD(n)R_C(n)=R_D(n) for every positive integer nn if and only if there exists an integer l1l\ge 1 such that r=22l1r=2^{2l}-1, m=22l+12m=2^{2l+1}-2, C=A2l(22l1+B2l)C=A_{2l}\cup (2^{2l}-1+B_{2l}) and D=B2l(22l1+A2l)D=B_{2l}\cup (2^{2l}-1+A_{2l}). This solved a problem of Chen and Lev. In this paper, we prove that, if CD=[0,m]{r}C \cup D=[0, m]\setminus \{r\} with 0<r<m0<r<m, CD=C \cap D=\emptyset and 0C0 \in C, then RC(n)=RD(n)R_{C}(n)=R_{D}(n) for any nonnegative integer nn if and only if there exists an integer l2l \geq 2 such that m=2lm=2^{l}, r=2l1r=2^{l-1}, C=Al1(2l1+1+Bl1)C=A_{l-1} \cup\left(2^{l-1}+1+B_{l-1}\right) and D=Bl1(2l1+1+Al1)D=B_{l-1} \cup\left(2^{l-1}+1+A_{l-1}\right).

Keywords

Cite

@article{arxiv.2111.07754,
  title  = {On the integer sets with the same representation functions},
  author = {Kai-Jie Jiao and Csaba Sándor and Quan-Hui Yang and Jun-Yu Zhou},
  journal= {arXiv preprint arXiv:2111.07754},
  year   = {2021}
}

Comments

9 pages