{"title":"关于繁忙的海狸边界的笔记","authors":"Tomás Schitter , Sergio Abriola , Nicolás González","doi":"10.1016/j.tcs.2025.115541","DOIUrl":null,"url":null,"abstract":"<div><div>We investigate the relationship between several variations of the Busy Beaver game proposed by Radó (1962), such as the <span><math><mrow><mi>s</mi><mi>p</mi><mi>a</mi><mi>c</mi><mi>e</mi><mo>(</mo><mi>n</mi><mo>)</mo></mrow></math></span> or the <span><math><mrow><mi>n</mi><mi>u</mi><mi>m</mi><mo>(</mo><mi>n</mi><mo>)</mo></mrow></math></span> functions, establishing new bounds on these functions in terms of each other, as well as some properties about their growth. We also introduce and investigate a new function, <span><math><mrow><mi>b</mi><mi>o</mi><mi>u</mi><mi>n</mi><mi>c</mi><mi>e</mi><mi>s</mi><mo>(</mo><mi>n</mi><mo>)</mo></mrow></math></span>, to this family of noncomputable functions. We give some specific values for <span><math><mrow><mi>b</mi><mi>o</mi><mi>u</mi><mi>n</mi><mi>c</mi><mi>e</mi><mi>s</mi><mo>(</mo><mi>n</mi><mo>)</mo></mrow></math></span>, as well as several results concerning its growth and its relationship to the previously studied Busy Beaver functions. We also investigate growth properties and relationships of these functions when considering Turing Machines with non-binary alphabets with a single blank symbol.</div></div>","PeriodicalId":49438,"journal":{"name":"Theoretical Computer Science","volume":"1057 ","pages":"Article 115541"},"PeriodicalIF":1.0000,"publicationDate":"2025-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"A note on busy beaver bounds\",\"authors\":\"Tomás Schitter , Sergio Abriola , Nicolás González\",\"doi\":\"10.1016/j.tcs.2025.115541\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><div>We investigate the relationship between several variations of the Busy Beaver game proposed by Radó (1962), such as the <span><math><mrow><mi>s</mi><mi>p</mi><mi>a</mi><mi>c</mi><mi>e</mi><mo>(</mo><mi>n</mi><mo>)</mo></mrow></math></span> or the <span><math><mrow><mi>n</mi><mi>u</mi><mi>m</mi><mo>(</mo><mi>n</mi><mo>)</mo></mrow></math></span> functions, establishing new bounds on these functions in terms of each other, as well as some properties about their growth. We also introduce and investigate a new function, <span><math><mrow><mi>b</mi><mi>o</mi><mi>u</mi><mi>n</mi><mi>c</mi><mi>e</mi><mi>s</mi><mo>(</mo><mi>n</mi><mo>)</mo></mrow></math></span>, to this family of noncomputable functions. We give some specific values for <span><math><mrow><mi>b</mi><mi>o</mi><mi>u</mi><mi>n</mi><mi>c</mi><mi>e</mi><mi>s</mi><mo>(</mo><mi>n</mi><mo>)</mo></mrow></math></span>, as well as several results concerning its growth and its relationship to the previously studied Busy Beaver functions. We also investigate growth properties and relationships of these functions when considering Turing Machines with non-binary alphabets with a single blank symbol.</div></div>\",\"PeriodicalId\":49438,\"journal\":{\"name\":\"Theoretical Computer Science\",\"volume\":\"1057 \",\"pages\":\"Article 115541\"},\"PeriodicalIF\":1.0000,\"publicationDate\":\"2025-09-10\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Theoretical Computer Science\",\"FirstCategoryId\":\"94\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S0304397525004797\",\"RegionNum\":4,\"RegionCategory\":\"计算机科学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q3\",\"JCRName\":\"COMPUTER SCIENCE, THEORY & METHODS\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Theoretical Computer Science","FirstCategoryId":"94","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0304397525004797","RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"COMPUTER SCIENCE, THEORY & METHODS","Score":null,"Total":0}
We investigate the relationship between several variations of the Busy Beaver game proposed by Radó (1962), such as the or the functions, establishing new bounds on these functions in terms of each other, as well as some properties about their growth. We also introduce and investigate a new function, , to this family of noncomputable functions. We give some specific values for , as well as several results concerning its growth and its relationship to the previously studied Busy Beaver functions. We also investigate growth properties and relationships of these functions when considering Turing Machines with non-binary alphabets with a single blank symbol.
期刊介绍:
Theoretical Computer Science is mathematical and abstract in spirit, but it derives its motivation from practical and everyday computation. Its aim is to understand the nature of computation and, as a consequence of this understanding, provide more efficient methodologies. All papers introducing or studying mathematical, logic and formal concepts and methods are welcome, provided that their motivation is clearly drawn from the field of computing.