{"title":"关于渐近理想级的上界","authors":"Saeed Jahandoust","doi":"10.1142/s021949882550272x","DOIUrl":null,"url":null,"abstract":"<p>Let <span><math altimg=\"eq-00003.gif\" display=\"inline\" overflow=\"scroll\"><mi>I</mi></math></span><span></span> and <span><math altimg=\"eq-00004.gif\" display=\"inline\" overflow=\"scroll\"><mi>J</mi></math></span><span></span> be ideals in a Noetherian ring <span><math altimg=\"eq-00005.gif\" display=\"inline\" overflow=\"scroll\"><mi>R</mi></math></span><span></span> and let <span><math altimg=\"eq-00006.gif\" display=\"inline\" overflow=\"scroll\"><msub><mrow><mi>x</mi></mrow><mrow><mn>1</mn></mrow></msub><mo>,</mo><mo>…</mo><mo>,</mo><msub><mrow><mi>x</mi></mrow><mrow><mi>n</mi></mrow></msub></math></span><span></span> be nonunits in <span><math altimg=\"eq-00007.gif\" display=\"inline\" overflow=\"scroll\"><mi>R</mi></math></span><span></span>. Then <span><math altimg=\"eq-00008.gif\" display=\"inline\" overflow=\"scroll\"><msub><mrow><mi>x</mi></mrow><mrow><mn>1</mn></mrow></msub><mo>,</mo><mo>…</mo><mo>,</mo><msub><mrow><mi>x</mi></mrow><mrow><mi>n</mi></mrow></msub></math></span><span></span> is said to be an asymptotic sequence over <span><math altimg=\"eq-00009.gif\" display=\"inline\" overflow=\"scroll\"><mi>I</mi></math></span><span></span> if <span><math altimg=\"eq-00010.gif\" display=\"inline\" overflow=\"scroll\"><mo stretchy=\"false\">(</mo><mi>I</mi><mo>,</mo><mo stretchy=\"false\">(</mo><msub><mrow><mi>x</mi></mrow><mrow><mn>1</mn></mrow></msub><mo>,</mo><mo>…</mo><mo>,</mo><msub><mrow><mi>x</mi></mrow><mrow><mi>n</mi></mrow></msub><mo stretchy=\"false\">)</mo><mo stretchy=\"false\">)</mo><mi>R</mi><mo>≠</mo><mi>R</mi></math></span><span></span> and if for all <span><math altimg=\"eq-00011.gif\" display=\"inline\" overflow=\"scroll\"><mn>1</mn><mo>≤</mo><mi>i</mi><mo>≤</mo><mi>n</mi></math></span><span></span>, <span><math altimg=\"eq-00012.gif\" display=\"inline\" overflow=\"scroll\"><msub><mrow><mi>x</mi></mrow><mrow><mi>i</mi></mrow></msub></math></span><span></span> is not in any associated prime of the integral closure <span><math altimg=\"eq-00013.gif\" display=\"inline\" overflow=\"scroll\"><mover accent=\"false\"><mrow><msup><mrow><mo stretchy=\"false\">(</mo><msub><mrow><mi>I</mi></mrow><mrow><mi>i</mi><mo stretchy=\"false\">−</mo><mn>1</mn></mrow></msub><mo stretchy=\"false\">)</mo></mrow><mrow><mi>m</mi></mrow></msup></mrow><mo accent=\"true\">¯</mo></mover></math></span><span></span> of <span><math altimg=\"eq-00014.gif\" display=\"inline\" overflow=\"scroll\"><msup><mrow><mo stretchy=\"false\">(</mo><msub><mrow><mi>I</mi></mrow><mrow><mi>i</mi><mo stretchy=\"false\">−</mo><mn>1</mn></mrow></msub><mo stretchy=\"false\">)</mo></mrow><mrow><mi>m</mi></mrow></msup><mo>=</mo><msup><mrow><mo stretchy=\"false\">(</mo><mi>I</mi><mo>,</mo><mo stretchy=\"false\">(</mo><msub><mrow><mi>x</mi></mrow><mrow><mn>1</mn></mrow></msub><mo>,</mo><mo>…</mo><mo>,</mo><msub><mrow><mi>x</mi></mrow><mrow><mi>i</mi><mo stretchy=\"false\">−</mo><mn>1</mn></mrow></msub><mo stretchy=\"false\">)</mo><mo stretchy=\"false\">)</mo></mrow><mrow><mi>m</mi></mrow></msup><mi>R</mi></math></span><span></span>, where <span><math altimg=\"eq-00015.gif\" display=\"inline\" overflow=\"scroll\"><mi>m</mi><mo>∈</mo><mi>ℕ</mi></math></span><span></span> is very large. Let <span><math altimg=\"eq-00016.gif\" display=\"inline\" overflow=\"scroll\"><msub><mrow><mo>agd</mo></mrow><mrow><mi>I</mi></mrow></msub><mo stretchy=\"false\">(</mo><mi>J</mi><mo stretchy=\"false\">)</mo></math></span><span></span> be the maximum number of elements in <span><math altimg=\"eq-00017.gif\" display=\"inline\" overflow=\"scroll\"><mi>J</mi></math></span><span></span> which form an asymptotic sequence over <span><math altimg=\"eq-00018.gif\" display=\"inline\" overflow=\"scroll\"><mi>I</mi></math></span><span></span>. It is characterized when <span><math altimg=\"eq-00019.gif\" display=\"inline\" overflow=\"scroll\"><msub><mrow><mo>agd</mo></mrow><mrow><mi>I</mi></mrow></msub><mo stretchy=\"false\">(</mo><mi>J</mi><mo stretchy=\"false\">)</mo></math></span><span></span> is equal to: (i) <span><math altimg=\"eq-00020.gif\" display=\"inline\" overflow=\"scroll\"><mi>ℓ</mi><mo stretchy=\"false\">(</mo><mi>J</mi><mo stretchy=\"false\">)</mo></math></span><span></span>, the analytic spread of <span><math altimg=\"eq-00021.gif\" display=\"inline\" overflow=\"scroll\"><mi>J</mi></math></span><span></span>, when <span><math altimg=\"eq-00022.gif\" display=\"inline\" overflow=\"scroll\"><mi>R</mi></math></span><span></span> is local; (ii) <span><math altimg=\"eq-00023.gif\" display=\"inline\" overflow=\"scroll\"><mo>ht</mo><mo stretchy=\"false\">(</mo><mi>I</mi><mo stretchy=\"false\">+</mo><mi>J</mi><mo stretchy=\"false\">)</mo><mo stretchy=\"false\">−</mo><mo>agd</mo><mo stretchy=\"false\">(</mo><mi>I</mi><mo stretchy=\"false\">)</mo></math></span><span></span>, where <span><math altimg=\"eq-00024.gif\" display=\"inline\" overflow=\"scroll\"><mo>agd</mo><mo stretchy=\"false\">(</mo><mi>I</mi><mo stretchy=\"false\">)</mo></math></span><span></span> is the maximum number of elements in <span><math altimg=\"eq-00025.gif\" display=\"inline\" overflow=\"scroll\"><mi>I</mi></math></span><span></span> which form an asymptotic sequence over <span><math altimg=\"eq-00026.gif\" display=\"inline\" overflow=\"scroll\"><mo stretchy=\"false\">(</mo><mn>0</mn><mo stretchy=\"false\">)</mo><mi>R</mi></math></span><span></span>, and several consequences of these characterizations are given. Finally, if <span><math altimg=\"eq-00027.gif\" display=\"inline\" overflow=\"scroll\"><mi>R</mi></math></span><span></span> is local with maximal ideal <span><math altimg=\"eq-00028.gif\" display=\"inline\" overflow=\"scroll\"><mi>𝔪</mi></math></span><span></span> then we reprove a known upper bound for <span><math altimg=\"eq-00029.gif\" display=\"inline\" overflow=\"scroll\"><msub><mrow><mo>agd</mo></mrow><mrow><mi>I</mi></mrow></msub><mo stretchy=\"false\">(</mo><mi>𝔪</mi><mo stretchy=\"false\">)</mo></math></span><span></span>.</p>","PeriodicalId":54888,"journal":{"name":"Journal of Algebra and Its Applications","volume":null,"pages":null},"PeriodicalIF":0.5000,"publicationDate":"2024-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"On upper bounds for asymptotic ideal-grade\",\"authors\":\"Saeed Jahandoust\",\"doi\":\"10.1142/s021949882550272x\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p>Let <span><math altimg=\\\"eq-00003.gif\\\" display=\\\"inline\\\" overflow=\\\"scroll\\\"><mi>I</mi></math></span><span></span> and <span><math altimg=\\\"eq-00004.gif\\\" display=\\\"inline\\\" overflow=\\\"scroll\\\"><mi>J</mi></math></span><span></span> be ideals in a Noetherian ring <span><math altimg=\\\"eq-00005.gif\\\" display=\\\"inline\\\" overflow=\\\"scroll\\\"><mi>R</mi></math></span><span></span> and let <span><math altimg=\\\"eq-00006.gif\\\" display=\\\"inline\\\" overflow=\\\"scroll\\\"><msub><mrow><mi>x</mi></mrow><mrow><mn>1</mn></mrow></msub><mo>,</mo><mo>…</mo><mo>,</mo><msub><mrow><mi>x</mi></mrow><mrow><mi>n</mi></mrow></msub></math></span><span></span> be nonunits in <span><math altimg=\\\"eq-00007.gif\\\" display=\\\"inline\\\" overflow=\\\"scroll\\\"><mi>R</mi></math></span><span></span>. Then <span><math altimg=\\\"eq-00008.gif\\\" display=\\\"inline\\\" overflow=\\\"scroll\\\"><msub><mrow><mi>x</mi></mrow><mrow><mn>1</mn></mrow></msub><mo>,</mo><mo>…</mo><mo>,</mo><msub><mrow><mi>x</mi></mrow><mrow><mi>n</mi></mrow></msub></math></span><span></span> is said to be an asymptotic sequence over <span><math altimg=\\\"eq-00009.gif\\\" display=\\\"inline\\\" overflow=\\\"scroll\\\"><mi>I</mi></math></span><span></span> if <span><math altimg=\\\"eq-00010.gif\\\" display=\\\"inline\\\" overflow=\\\"scroll\\\"><mo stretchy=\\\"false\\\">(</mo><mi>I</mi><mo>,</mo><mo stretchy=\\\"false\\\">(</mo><msub><mrow><mi>x</mi></mrow><mrow><mn>1</mn></mrow></msub><mo>,</mo><mo>…</mo><mo>,</mo><msub><mrow><mi>x</mi></mrow><mrow><mi>n</mi></mrow></msub><mo stretchy=\\\"false\\\">)</mo><mo stretchy=\\\"false\\\">)</mo><mi>R</mi><mo>≠</mo><mi>R</mi></math></span><span></span> and if for all <span><math altimg=\\\"eq-00011.gif\\\" display=\\\"inline\\\" overflow=\\\"scroll\\\"><mn>1</mn><mo>≤</mo><mi>i</mi><mo>≤</mo><mi>n</mi></math></span><span></span>, <span><math altimg=\\\"eq-00012.gif\\\" display=\\\"inline\\\" overflow=\\\"scroll\\\"><msub><mrow><mi>x</mi></mrow><mrow><mi>i</mi></mrow></msub></math></span><span></span> is not in any associated prime of the integral closure <span><math altimg=\\\"eq-00013.gif\\\" display=\\\"inline\\\" overflow=\\\"scroll\\\"><mover accent=\\\"false\\\"><mrow><msup><mrow><mo stretchy=\\\"false\\\">(</mo><msub><mrow><mi>I</mi></mrow><mrow><mi>i</mi><mo stretchy=\\\"false\\\">−</mo><mn>1</mn></mrow></msub><mo stretchy=\\\"false\\\">)</mo></mrow><mrow><mi>m</mi></mrow></msup></mrow><mo accent=\\\"true\\\">¯</mo></mover></math></span><span></span> of <span><math altimg=\\\"eq-00014.gif\\\" display=\\\"inline\\\" overflow=\\\"scroll\\\"><msup><mrow><mo stretchy=\\\"false\\\">(</mo><msub><mrow><mi>I</mi></mrow><mrow><mi>i</mi><mo stretchy=\\\"false\\\">−</mo><mn>1</mn></mrow></msub><mo stretchy=\\\"false\\\">)</mo></mrow><mrow><mi>m</mi></mrow></msup><mo>=</mo><msup><mrow><mo stretchy=\\\"false\\\">(</mo><mi>I</mi><mo>,</mo><mo stretchy=\\\"false\\\">(</mo><msub><mrow><mi>x</mi></mrow><mrow><mn>1</mn></mrow></msub><mo>,</mo><mo>…</mo><mo>,</mo><msub><mrow><mi>x</mi></mrow><mrow><mi>i</mi><mo stretchy=\\\"false\\\">−</mo><mn>1</mn></mrow></msub><mo stretchy=\\\"false\\\">)</mo><mo stretchy=\\\"false\\\">)</mo></mrow><mrow><mi>m</mi></mrow></msup><mi>R</mi></math></span><span></span>, where <span><math altimg=\\\"eq-00015.gif\\\" display=\\\"inline\\\" overflow=\\\"scroll\\\"><mi>m</mi><mo>∈</mo><mi>ℕ</mi></math></span><span></span> is very large. Let <span><math altimg=\\\"eq-00016.gif\\\" display=\\\"inline\\\" overflow=\\\"scroll\\\"><msub><mrow><mo>agd</mo></mrow><mrow><mi>I</mi></mrow></msub><mo stretchy=\\\"false\\\">(</mo><mi>J</mi><mo stretchy=\\\"false\\\">)</mo></math></span><span></span> be the maximum number of elements in <span><math altimg=\\\"eq-00017.gif\\\" display=\\\"inline\\\" overflow=\\\"scroll\\\"><mi>J</mi></math></span><span></span> which form an asymptotic sequence over <span><math altimg=\\\"eq-00018.gif\\\" display=\\\"inline\\\" overflow=\\\"scroll\\\"><mi>I</mi></math></span><span></span>. It is characterized when <span><math altimg=\\\"eq-00019.gif\\\" display=\\\"inline\\\" overflow=\\\"scroll\\\"><msub><mrow><mo>agd</mo></mrow><mrow><mi>I</mi></mrow></msub><mo stretchy=\\\"false\\\">(</mo><mi>J</mi><mo stretchy=\\\"false\\\">)</mo></math></span><span></span> is equal to: (i) <span><math altimg=\\\"eq-00020.gif\\\" display=\\\"inline\\\" overflow=\\\"scroll\\\"><mi>ℓ</mi><mo stretchy=\\\"false\\\">(</mo><mi>J</mi><mo stretchy=\\\"false\\\">)</mo></math></span><span></span>, the analytic spread of <span><math altimg=\\\"eq-00021.gif\\\" display=\\\"inline\\\" overflow=\\\"scroll\\\"><mi>J</mi></math></span><span></span>, when <span><math altimg=\\\"eq-00022.gif\\\" display=\\\"inline\\\" overflow=\\\"scroll\\\"><mi>R</mi></math></span><span></span> is local; (ii) <span><math altimg=\\\"eq-00023.gif\\\" display=\\\"inline\\\" overflow=\\\"scroll\\\"><mo>ht</mo><mo stretchy=\\\"false\\\">(</mo><mi>I</mi><mo stretchy=\\\"false\\\">+</mo><mi>J</mi><mo stretchy=\\\"false\\\">)</mo><mo stretchy=\\\"false\\\">−</mo><mo>agd</mo><mo stretchy=\\\"false\\\">(</mo><mi>I</mi><mo stretchy=\\\"false\\\">)</mo></math></span><span></span>, where <span><math altimg=\\\"eq-00024.gif\\\" display=\\\"inline\\\" overflow=\\\"scroll\\\"><mo>agd</mo><mo stretchy=\\\"false\\\">(</mo><mi>I</mi><mo stretchy=\\\"false\\\">)</mo></math></span><span></span> is the maximum number of elements in <span><math altimg=\\\"eq-00025.gif\\\" display=\\\"inline\\\" overflow=\\\"scroll\\\"><mi>I</mi></math></span><span></span> which form an asymptotic sequence over <span><math altimg=\\\"eq-00026.gif\\\" display=\\\"inline\\\" overflow=\\\"scroll\\\"><mo stretchy=\\\"false\\\">(</mo><mn>0</mn><mo stretchy=\\\"false\\\">)</mo><mi>R</mi></math></span><span></span>, and several consequences of these characterizations are given. Finally, if <span><math altimg=\\\"eq-00027.gif\\\" display=\\\"inline\\\" overflow=\\\"scroll\\\"><mi>R</mi></math></span><span></span> is local with maximal ideal <span><math altimg=\\\"eq-00028.gif\\\" display=\\\"inline\\\" overflow=\\\"scroll\\\"><mi>𝔪</mi></math></span><span></span> then we reprove a known upper bound for <span><math altimg=\\\"eq-00029.gif\\\" display=\\\"inline\\\" overflow=\\\"scroll\\\"><msub><mrow><mo>agd</mo></mrow><mrow><mi>I</mi></mrow></msub><mo stretchy=\\\"false\\\">(</mo><mi>𝔪</mi><mo stretchy=\\\"false\\\">)</mo></math></span><span></span>.</p>\",\"PeriodicalId\":54888,\"journal\":{\"name\":\"Journal of Algebra and Its Applications\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":0.5000,\"publicationDate\":\"2024-05-23\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Journal of Algebra and Its Applications\",\"FirstCategoryId\":\"100\",\"ListUrlMain\":\"https://doi.org/10.1142/s021949882550272x\",\"RegionNum\":3,\"RegionCategory\":\"数学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q3\",\"JCRName\":\"MATHEMATICS\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Algebra and Its Applications","FirstCategoryId":"100","ListUrlMain":"https://doi.org/10.1142/s021949882550272x","RegionNum":3,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"MATHEMATICS","Score":null,"Total":0}
引用次数: 0
摘要
设 I 和 J 是诺特环 R 中的理想,设 x1,...,xn 是 R 中的非单元。如果 (I,(x1,...,xn))R≠R 并且对于所有 1≤i≤n, xi 不在 (Ii-1)m=(I,(x1,...,xi-1))mR 的积分闭包 (Ii-1)m¯ 的任何相关素数中,其中 m∈ℕ 非常大,那么 x1,...,xn 可以说是 I 上的渐近序列。设 agdI(J) 是 J 中构成 I 上渐近序列的元素的最大数目:(i) ℓ(J),J 的解析展宽,当 R 是局部时;(ii) ht(I+J)-agd(I),其中 agd(I) 是 I 中构成 (0)R 上渐近序列的元素的最大数目,并给出了这些特征的若干后果。最后,如果 R 是局部最大理想ᵒ,那么我们将重新证明 agdI(𝔪) 的已知上限。
Let and be ideals in a Noetherian ring and let be nonunits in . Then is said to be an asymptotic sequence over if and if for all , is not in any associated prime of the integral closure of , where is very large. Let be the maximum number of elements in which form an asymptotic sequence over . It is characterized when is equal to: (i) , the analytic spread of , when is local; (ii) , where is the maximum number of elements in which form an asymptotic sequence over , and several consequences of these characterizations are given. Finally, if is local with maximal ideal then we reprove a known upper bound for .
期刊介绍:
The Journal of Algebra and Its Applications will publish papers both on theoretical and on applied aspects of Algebra. There is special interest in papers that point out innovative links between areas of Algebra and fields of application. As the field of Algebra continues to experience tremendous growth and diversification, we intend to provide the mathematical community with a central source for information on both the theoretical and the applied aspects of the discipline. While the journal will be primarily devoted to the publication of original research, extraordinary expository articles that encourage communication between algebraists and experts on areas of application as well as those presenting the state of the art on a given algebraic sub-discipline will be considered.