发布求助
文献互助 智能选刊 最新文献

Czechoslovak Mathematical Journal最新文献

筛选
英文 中文
On the signless Laplacian and normalized signless Laplacian spreads of graphs 图的无符号拉普拉斯扩展和归一化无符号拉普拉斯扩展
IF 0.5 4区 数学
Czechoslovak Mathematical Journal Pub Date : 2023-02-06 DOI: 10.21136/CMJ.2023.0005-22
E. Milovanovic, Ş. B. Bozkurt Altindağ, M. Matejic, I. Milovanovic
{"title":"On the signless Laplacian and normalized signless Laplacian spreads of graphs","authors":"E. Milovanovic, Ş. B. Bozkurt Altindağ, M. Matejic, I. Milovanovic","doi":"10.21136/CMJ.2023.0005-22","DOIUrl":"https://doi.org/10.21136/CMJ.2023.0005-22","url":null,"abstract":"Let G = (V, E), V = {v1, v2, …, vn}, be a simple connected graph with n vertices, m edges and a sequence of vertex degrees d1 ≽ d2 ≽ … ≽ dn. Denote by A and D the adjacency matrix and diagonal vertex degree matrix of G, respectively. The signless Laplacian of G is defined as L+ = D + A and the normalized signless Laplacian matrix as r(G)=γ2+/γn+documentclass[12pt]{minimal} usepackage{amsmath} usepackage{wasysym} usepackage{amsfonts} usepackage{amssymb} usepackage{amsbsy} usepackage{mathrsfs} usepackage{upgreek} setlength{oddsidemargin}{-69pt} begin{document}$$rleft( G right) = gamma _2^ + /gamma _n^ + $$end{document}. The normalized signless Laplacian spreads of a connected nonbipartite graph G are defined as l(G)=γ2+−γn+documentclass[12pt]{minimal} usepackage{amsmath} usepackage{wasysym} usepackage{amsfonts} usepackage{amssymb} usepackage{amsbsy} usepackage{mathrsfs} usepackage{upgreek} setlength{oddsidemargin}{-69pt} begin{document}$$lleft( G right) = gamma _2^ + - gamma _n^ + $$end{document}, where γ1+⩾γ2+⩾...⩾γn+⩾0documentclass[12pt]{minimal} usepackage{amsmath} usepackage{wasysym} usepackage{amsfonts} usepackage{amssymb} usepackage{amsbsy} usepackage{mathrsfs} usepackage{upgreek} setlength{oddsidemargin}{-69pt} begin{document}$$gamma _1^ + geqslant gamma _2^ + geqslant ldots geqslant gamma _n^ + geqslant 0$$end{document} are eigenvalues of ℒ+documentclass[12pt]{minimal} usepackage{amsmath} usepackage{wasysym} usepackage{amsfonts} usepackage{amssymb} usepackage{amsbsy} usepackage{mathrsfs} usepackage{upgreek} setlength{oddsidemargin}{-69pt} begin{document}$${{cal L}^ + }$$end{document}. We establish sharp lower and upper bounds for the normalized signless Laplacian spreads of connected graphs. In addition, we present a better lower bound on the signless Laplacian spread.","PeriodicalId":50596,"journal":{"name":"Czechoslovak Mathematical Journal","volume":"73 1","pages":"499 - 511"},"PeriodicalIF":0.5,"publicationDate":"2023-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48304773","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
A note on rational surgeries on a Hopf link Hopf链接上关于理性手术的说明
IF 0.5 4区 数学
Czechoslovak Mathematical Journal Pub Date : 2023-02-06 DOI: 10.21136/CMJ.2023.0144-22
V. Bojković, Jovana Nikolić, M. Zekic
{"title":"A note on rational surgeries on a Hopf link","authors":"V. Bojković, Jovana Nikolić, M. Zekic","doi":"10.21136/CMJ.2023.0144-22","DOIUrl":"https://doi.org/10.21136/CMJ.2023.0144-22","url":null,"abstract":"It is clear that every rational surgery on a Hopf link in 3-sphere is a lens space surgery. In this note we give an explicit computation which lens space is a resulting manifold. The main tool we use is the calculus of continued fractions. As a corollary, we recover the (well-known) result on the criterion for when rational surgery on a Hopf link gives the 3-sphere.","PeriodicalId":50596,"journal":{"name":"Czechoslovak Mathematical Journal","volume":"73 1","pages":"603 - 611"},"PeriodicalIF":0.5,"publicationDate":"2023-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46978568","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
A geometric construction for spectrally arbitrary sign pattern matrices and the 2n-conjecture 谱任意符号模式矩阵的几何构造及2n猜想
IF 0.5 4区 数学
Czechoslovak Mathematical Journal Pub Date : 2023-02-02 DOI: 10.21136/CMJ.2023.0132-22
D. Jadhav, R. Deore
{"title":"A geometric construction for spectrally arbitrary sign pattern matrices and the 2n-conjecture","authors":"D. Jadhav, R. Deore","doi":"10.21136/CMJ.2023.0132-22","DOIUrl":"https://doi.org/10.21136/CMJ.2023.0132-22","url":null,"abstract":"We develop a geometric method for studying the spectral arbitrariness of a given sign pattern matrix. The method also provides a computational way of computing matrix realizations for a given characteristic polynomial. We also provide a partial answer to 2n-conjecture. We determine that the 2n-conjecture holds for the class of spectrally arbitrary patterns that have a column or row with at least n − 1 nonzero entries.","PeriodicalId":50596,"journal":{"name":"Czechoslovak Mathematical Journal","volume":"73 1","pages":"565 - 580"},"PeriodicalIF":0.5,"publicationDate":"2023-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43215503","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Commutative graded-S-coherent rings 交换梯度s -相干环
IF 0.5 4区 数学
Czechoslovak Mathematical Journal Pub Date : 2023-02-02 DOI: 10.21136/CMJ.2023.0130-22
Anass Assarrar, N. Mahdou, Ünsal Tekir, Suat Koç
{"title":"Commutative graded-S-coherent rings","authors":"Anass Assarrar, N. Mahdou, Ünsal Tekir, Suat Koç","doi":"10.21136/CMJ.2023.0130-22","DOIUrl":"https://doi.org/10.21136/CMJ.2023.0130-22","url":null,"abstract":"Recently, motivated by Anderson, Dumitrescu’s S-finiteness, D. Bennis, M. El Hajoui (2018) introduced the notion of S-coherent rings, which is the S-version of coherent rings. Let R=⊕α∈GRαdocumentclass[12pt]{minimal} usepackage{amsmath} usepackage{wasysym} usepackage{amsfonts} usepackage{amssymb} usepackage{amsbsy} usepackage{mathrsfs} usepackage{upgreek} setlength{oddsidemargin}{-69pt} begin{document}$$R = mathop oplus limits_{alpha in G} {R_alpha }$$end{document} be a commutative ring with unity graded by an arbitrary commutative monoid G, and S a multiplicatively closed subset of nonzero homogeneous elements of R. We define R to be graded-S-coherent ring if every finitely generated homogeneous ideal of R is S-finitely presented. The purpose of this paper is to give the graded version of several results proved in D. Bennis, M. El Hajoui (2018). We show the nontriviality of our generalization by giving an example of a graded-S-coherent ring which is not S-coherent and as a special case of our study, we give the graded version of the Chase’s characterization of S-coherent rings.","PeriodicalId":50596,"journal":{"name":"Czechoslovak Mathematical Journal","volume":"73 1","pages":"553 - 564"},"PeriodicalIF":0.5,"publicationDate":"2023-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44978792","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Sum of higher divisor function with prime summands 高因子函数与素数和的和
IF 0.5 4区 数学
Czechoslovak Mathematical Journal Pub Date : 2023-01-31 DOI: 10.21136/CMJ.2023.0206-22
Yuchen Ding, G. Zhou
{"title":"Sum of higher divisor function with prime summands","authors":"Yuchen Ding, G. Zhou","doi":"10.21136/CMJ.2023.0206-22","DOIUrl":"https://doi.org/10.21136/CMJ.2023.0206-22","url":null,"abstract":"Let l ≽ 2 be an integer. Recently, Hu and Lü offered the asymptotic formula for the sum of the higher divisor function documentclass[12pt]{minimal} usepackage{amsmath} usepackage{wasysym} usepackage{amsfonts} usepackage{amssymb} usepackage{amsbsy} usepackage{mathrsfs} usepackage{upgreek} setlength{oddsidemargin}{-69pt} begin{document}$$sumlimits_{1 leqslant {n_1},{n_2},...,{n_1} leqslant {x^{1/2}}} {{tau _k}(n_1^2 + n_2^2 + ... + n_1^2),} $$end{document} where τk (n) represents the kth divisor function. We give the Goldbach-type analogy of their result. That is to say, we investigate the asymptotic behavior of the sum documentclass[12pt]{minimal} usepackage{amsmath} usepackage{wasysym} usepackage{amsfonts} usepackage{amssymb} usepackage{amsbsy} usepackage{mathrsfs} usepackage{upgreek} setlength{oddsidemargin}{-69pt} begin{document}$$sumlimits_{1 leqslant {p_1},p2,...,{p_1} leqslant x} {{tau _k}({p_1} + {p_2} + ... + {p_l}),} $$end{document} where p1, p2, …, pl are prime variables.","PeriodicalId":50596,"journal":{"name":"Czechoslovak Mathematical Journal","volume":"73 1","pages":"621 - 631"},"PeriodicalIF":0.5,"publicationDate":"2023-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44027758","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Exponential stability conditions for non-autonomous differential equations with unbounded commutators in a Banach space Banach空间中具有无界交换子的非自治微分方程的指数稳定性条件
IF 0.5 4区 数学
Czechoslovak Mathematical Journal Pub Date : 2023-01-23 DOI: 10.21136/CMJ.2023.0188-21
M. Gil'
{"title":"Exponential stability conditions for non-autonomous differential equations with unbounded commutators in a Banach space","authors":"M. Gil'","doi":"10.21136/CMJ.2023.0188-21","DOIUrl":"https://doi.org/10.21136/CMJ.2023.0188-21","url":null,"abstract":"We consider the equation dy(t)/dt = (A + B(t))y(t) (t ≽ 0), where A is the generator of an analytic semigroup (eAt)t≽0 on a Banach space χ, B(t) is a variable bounded operator in χ. It is assumed that the commutator K(t) = AB(t) − B(t)A has the following property: there is a linear operator S having a bounded left-inverse operator Sl−1documentclass[12pt]{minimal} usepackage{amsmath} usepackage{wasysym} usepackage{amsfonts} usepackage{amssymb} usepackage{amsbsy} usepackage{mathrsfs} usepackage{upgreek} setlength{oddsidemargin}{-69pt} begin{document}$$S_l^{ - 1}$$end{document} such that ∥SeAt∥ is integrable and the operator K(t)Sl−1documentclass[12pt]{minimal} usepackage{amsmath} usepackage{wasysym} usepackage{amsfonts} usepackage{amssymb} usepackage{amsbsy} usepackage{mathrsfs} usepackage{upgreek} setlength{oddsidemargin}{-69pt} begin{document}$$Kleft( t right)S_l^{ - 1}$$end{document} is bounded. Under these conditions an exponential stability test is derived. As an example we consider a coupled system of parabolic equations.","PeriodicalId":50596,"journal":{"name":"Czechoslovak Mathematical Journal","volume":"73 1","pages":"355 - 366"},"PeriodicalIF":0.5,"publicationDate":"2023-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42755119","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Some homological properties of amalgamated modules along an ideal 沿理想方向合并模的若干同调性质
IF 0.5 4区 数学
Czechoslovak Mathematical Journal Pub Date : 2023-01-18 DOI: 10.21136/CMJ.2023.0411-21
Hanieh Shoar, M. Salimi, A. Tehranian, H. Rasouli, E. Tavasoli
{"title":"Some homological properties of amalgamated modules along an ideal","authors":"Hanieh Shoar, M. Salimi, A. Tehranian, H. Rasouli, E. Tavasoli","doi":"10.21136/CMJ.2023.0411-21","DOIUrl":"https://doi.org/10.21136/CMJ.2023.0411-21","url":null,"abstract":"Let R and S be commutative rings with identity, J be an ideal of S, f: R → S be a ring homomorphism, M be an R-module, N be an S-module, and let φ: M → N be an R-homomorphism. The amalgamation of R with S along J with respect to f denoted by R ⨝fJ was introduced by M. D’Anna et al. (2010). Recently, R. El Khalfaoui et al. (2021) introduced a special kind of (R ⨝fJ)-module called the amalgamation of M and N along J with respect to φ, and denoted by M ⨝φJN. We study some homological properties of the (R ⨝fJ)-module M ⨝φJN. Among other results, we investigate projectivity, flatness, injectivity, Cohen-Macaulayness, and prime property of the (R ⨝fJ)-module M ⨝φJN in connection to their corresponding properties of the R-modules M and JN.","PeriodicalId":50596,"journal":{"name":"Czechoslovak Mathematical Journal","volume":"73 1","pages":"475 - 486"},"PeriodicalIF":0.5,"publicationDate":"2023-01-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48868842","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Relative Auslander bijection in n-exangulated categories 在n-膨化范畴中相对澳洲双射
IF 0.5 4区 数学
Czechoslovak Mathematical Journal Pub Date : 2023-01-18 DOI: 10.21136/CMJ.2023.0127-22
Jian He, Jing He, Panyue Zhou
{"title":"Relative Auslander bijection in n-exangulated categories","authors":"Jian He, Jing He, Panyue Zhou","doi":"10.21136/CMJ.2023.0127-22","DOIUrl":"https://doi.org/10.21136/CMJ.2023.0127-22","url":null,"abstract":"The aim of this article is to study the relative Auslander bijection in n-exangulated categories. More precisely, we introduce the notion of generalized Auslander-Reiten-Serre duality and exploit a bijection triangle, which involves the generalized Auslander-Reiten-Serre duality and the restricted Auslander bijection relative to the subfunctor. As an application, this result generalizes the work by Zhao in extriangulated categories.","PeriodicalId":50596,"journal":{"name":"Czechoslovak Mathematical Journal","volume":"73 1","pages":"525 - 552"},"PeriodicalIF":0.5,"publicationDate":"2023-01-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43662055","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Another version of cosupport in D(R) D(R)中的另一个版本的共支持
IF 0.5 4区 数学
Czechoslovak Mathematical Journal Pub Date : 2023-01-05 DOI: 10.21136/CMJ.2023.0282-21
Junquan Qin, Xiaoyan Yang
{"title":"Another version of cosupport in D(R)","authors":"Junquan Qin, Xiaoyan Yang","doi":"10.21136/CMJ.2023.0282-21","DOIUrl":"https://doi.org/10.21136/CMJ.2023.0282-21","url":null,"abstract":"The goal of the article is to develop a theory dual to that of support in the derived category D(R). This is done by introducing ‘big’ and ‘small’ cosupport for complexes that are different from the cosupport in D. J. Benson, S. B. Iyengar, H. Krause (2012). We give some properties for cosupport that are similar, or rather dual, to those of support for complexes, study some relations between ‘big’ and ‘small’ cosupport and give some comparisons of support and cosupport. Finally, we investigate the dual notion of associated primes.","PeriodicalId":50596,"journal":{"name":"Czechoslovak Mathematical Journal","volume":"73 1","pages":"431 - 452"},"PeriodicalIF":0.5,"publicationDate":"2023-01-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43279098","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
On wsq-primary ideals 关于wsq初理想
IF 0.5 4区 数学
Czechoslovak Mathematical Journal Pub Date : 2023-01-03 DOI: 10.21136/CMJ.2023.0259-21
Emel Aslankarayiğit Uğurlu, E. M. Bouba, Ünsal Tekir, Suat Koç
{"title":"On wsq-primary ideals","authors":"Emel Aslankarayiğit Uğurlu, E. M. Bouba, Ünsal Tekir, Suat Koç","doi":"10.21136/CMJ.2023.0259-21","DOIUrl":"https://doi.org/10.21136/CMJ.2023.0259-21","url":null,"abstract":"We introduce weakly strongly quasi-primary (briefly, wsq-primary) ideals in commutative rings. Let R be a commutative ring with a nonzero identity and Q a proper ideal of R. The proper ideal Q is said to be a weakly strongly quasi-primary ideal if whenever 0 ≠ ab ∈ Q for some a, b ∈ R, then a2 ∈ Q or b∈Qdocumentclass[12pt]{minimal} usepackage{amsmath} usepackage{wasysym} usepackage{amsfonts} usepackage{amssymb} usepackage{amsbsy} usepackage{mathrsfs} usepackage{upgreek} setlength{oddsidemargin}{-69pt} begin{document}$$b in sqrt Q $$end{document}. Many examples and properties of wsq-primary ideals are given. Also, we characterize nonlocal Noetherian von Neumann regular rings, fields, nonlocal rings over which every proper ideal is wsq-primary, and zero dimensional rings over which every proper ideal is wsq-primary. Finally, we study finite union of wsq-primary ideals.","PeriodicalId":50596,"journal":{"name":"Czechoslovak Mathematical Journal","volume":"73 1","pages":"415 - 429"},"PeriodicalIF":0.5,"publicationDate":"2023-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43483450","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
首页 上一页 下一页 尾页
0
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
提示
您的信息不完整，为了账户安全，请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
现在去查看 取消
×
提示
确定
请完成安全验证×
相关产品
×
本文献相关产品
联系我们：info@booksci.cn Book学术提供免费学术资源搜索服务，方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。 Copyright © 2023 布克学术 All rights reserved.
京ICP备2023020795号-1
ghs 京公网安备 11010802042870号
Book学术文献互助
Book学术文献互助群
群 号：481959085
Book学术官方微信