{"title":"没有流行差异的模式","authors":"A. Sah, Mehtaab Sawhney, Yufei Zhao","doi":"10.19086/da.25317","DOIUrl":null,"url":null,"abstract":"Which finite sets $P \\subseteq \\mathbb{Z}^r$ with $|P| \\ge 3$ have the following property: for every $A \\subseteq [N]^r$, there is some nonzero integer $d$ such that $A$ contains $(\\alpha^{|P|} - o(1))N^r$ translates of $d \\cdot P = \\{d p : p \\in P\\}$, where $\\alpha = |A|/N^r$? \nGreen showed that all 3-point $P \\subseteq \\mathbb{Z}$ have the above property. Green and Tao showed that 4-point sets of the form $P = \\{a, a+b, a+c, a+b+c\\} \\subseteq \\mathbb{Z}$ also have the property. We show that no other sets have the above property. Furthermore, for various $P$, we provide new upper bounds on the number of translates of $d \\cdot P$ that one can guarantee to find.","PeriodicalId":8442,"journal":{"name":"arXiv: Combinatorics","volume":"1 1","pages":""},"PeriodicalIF":0.0000,"publicationDate":"2020-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"4","resultStr":"{\"title\":\"Patterns without a popular difference\",\"authors\":\"A. Sah, Mehtaab Sawhney, Yufei Zhao\",\"doi\":\"10.19086/da.25317\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"Which finite sets $P \\\\subseteq \\\\mathbb{Z}^r$ with $|P| \\\\ge 3$ have the following property: for every $A \\\\subseteq [N]^r$, there is some nonzero integer $d$ such that $A$ contains $(\\\\alpha^{|P|} - o(1))N^r$ translates of $d \\\\cdot P = \\\\{d p : p \\\\in P\\\\}$, where $\\\\alpha = |A|/N^r$? \\nGreen showed that all 3-point $P \\\\subseteq \\\\mathbb{Z}$ have the above property. Green and Tao showed that 4-point sets of the form $P = \\\\{a, a+b, a+c, a+b+c\\\\} \\\\subseteq \\\\mathbb{Z}$ also have the property. We show that no other sets have the above property. Furthermore, for various $P$, we provide new upper bounds on the number of translates of $d \\\\cdot P$ that one can guarantee to find.\",\"PeriodicalId\":8442,\"journal\":{\"name\":\"arXiv: Combinatorics\",\"volume\":\"1 1\",\"pages\":\"\"},\"PeriodicalIF\":0.0000,\"publicationDate\":\"2020-04-16\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"4\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"arXiv: Combinatorics\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://doi.org/10.19086/da.25317\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"\",\"JCRName\":\"\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"arXiv: Combinatorics","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.19086/da.25317","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
Which finite sets $P \subseteq \mathbb{Z}^r$ with $|P| \ge 3$ have the following property: for every $A \subseteq [N]^r$, there is some nonzero integer $d$ such that $A$ contains $(\alpha^{|P|} - o(1))N^r$ translates of $d \cdot P = \{d p : p \in P\}$, where $\alpha = |A|/N^r$?
Green showed that all 3-point $P \subseteq \mathbb{Z}$ have the above property. Green and Tao showed that 4-point sets of the form $P = \{a, a+b, a+c, a+b+c\} \subseteq \mathbb{Z}$ also have the property. We show that no other sets have the above property. Furthermore, for various $P$, we provide new upper bounds on the number of translates of $d \cdot P$ that one can guarantee to find.