Pub Date : 2024-07-16DOI: 10.1007/s11587-024-00879-0
Baojun Li, Hao Wu, Libo Zhao, Lu Gong
{"title":"The norm of the derived series in a finite group","authors":"Baojun Li, Hao Wu, Libo Zhao, Lu Gong","doi":"10.1007/s11587-024-00879-0","DOIUrl":"https://doi.org/10.1007/s11587-024-00879-0","url":null,"abstract":"","PeriodicalId":21373,"journal":{"name":"Ricerche di Matematica","volume":null,"pages":null},"PeriodicalIF":1.1,"publicationDate":"2024-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141644172","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}
Pub Date : 2024-07-16DOI: 10.1007/s11587-024-00877-2
Tao Xu, Heguo Liu, Ruihong Wang
{"title":"Automorphisms fixing every normal subgroup of an extraspecial $$mathbb {Z}$$-group","authors":"Tao Xu, Heguo Liu, Ruihong Wang","doi":"10.1007/s11587-024-00877-2","DOIUrl":"https://doi.org/10.1007/s11587-024-00877-2","url":null,"abstract":"","PeriodicalId":21373,"journal":{"name":"Ricerche di Matematica","volume":null,"pages":null},"PeriodicalIF":1.1,"publicationDate":"2024-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141643596","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}
Pub Date : 2024-07-16DOI: 10.1007/s11587-024-00874-5
Sakthidevi Kaliyaperumal, Kalyani Desikan
{"title":"$$D_{alpha }$$-spectrum of subdivision join of graphs","authors":"Sakthidevi Kaliyaperumal, Kalyani Desikan","doi":"10.1007/s11587-024-00874-5","DOIUrl":"https://doi.org/10.1007/s11587-024-00874-5","url":null,"abstract":"","PeriodicalId":21373,"journal":{"name":"Ricerche di Matematica","volume":null,"pages":null},"PeriodicalIF":1.1,"publicationDate":"2024-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141641128","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}
Pub Date : 2024-07-15DOI: 10.1007/s11587-024-00875-4
A. Fonda, Natnael Gezahegn Mamo, Andrea Sfecci
{"title":"An extension of the Poincaré–Birkhoff Theorem to systems involving Landesman–Lazer conditions","authors":"A. Fonda, Natnael Gezahegn Mamo, Andrea Sfecci","doi":"10.1007/s11587-024-00875-4","DOIUrl":"https://doi.org/10.1007/s11587-024-00875-4","url":null,"abstract":"","PeriodicalId":21373,"journal":{"name":"Ricerche di Matematica","volume":null,"pages":null},"PeriodicalIF":1.1,"publicationDate":"2024-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141648682","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}
Pub Date : 2024-07-04DOI: 10.1007/s11587-024-00871-8
Antongiulio Fornasiero, Giuseppina Terzo
We investigate the zero sets of complex exponential polynomials in one variable with only one iteration. We characterize when such polynomials have the same zero set in terms of the radical ideals. Moreover we give a bound on the multiplicity of zeros.
{"title":"A note on exponential polynomials","authors":"Antongiulio Fornasiero, Giuseppina Terzo","doi":"10.1007/s11587-024-00871-8","DOIUrl":"https://doi.org/10.1007/s11587-024-00871-8","url":null,"abstract":"<p>We investigate the zero sets of complex exponential polynomials in one variable with only one iteration. We characterize when such polynomials have the same zero set in terms of the radical ideals. Moreover we give a bound on the multiplicity of zeros.</p>","PeriodicalId":21373,"journal":{"name":"Ricerche di Matematica","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2024-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141550345","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}
Pub Date : 2024-07-03DOI: 10.1007/s11587-024-00873-6
Weicheng Zheng, Wei Meng
Let G be a finite group. A group G is called a T group if its every subnormal subgroup is normal. A subgroup H of G is called Hall normally embedded in G if H is a Hall subgroup of (H^G), where (H^G) is the normal closure of H in G. Using the notion of Hall normally embedded subgroups, we characterize supersolvable groups and solvable T-group. First, we prove that if every cyclic subgroup of G of order prime or 4 is Hall normally embedded in G, then G is supersolvable with a well defined structure. Second, we prove that an A-group G is supersolvable if and only if its Sylow subgroups are products of cyclic Hall normally embedded subgroups of G. Final, we show that G is a solvable T-group if and only if every p-subgroup of G is Hall normally embedded in G, for all primes (pin pi (G)).
设 G 是一个有限群。如果一个群 G 的每个子正常子群都是正常的,那么这个群就叫做 T 群。如果 H 是 (H^G) 的霍尔子群,其中 (H^G) 是 H 在 G 中的常闭,那么 G 的一个子群 H 称为霍尔常嵌于 G。首先,我们证明,如果 G 的每个素数或 4 阶循环子群都是霍尔常嵌于 G 的,那么 G 是具有定义明确的结构的可超溶群。其次,我们证明了当且仅当一个 A 群 G 的 Sylow 子群是 G 的循环霍尔常内含子群的乘积时,G 是可解的。最后,我们证明了当且仅当 G 的每个 p 子群都是霍尔常内含于 G 时,对于所有素数 (pin pi (G)),G 是可解的 T 群。
{"title":"Finite supersolvable groups and Hall normally embedded subgroups of prime power order","authors":"Weicheng Zheng, Wei Meng","doi":"10.1007/s11587-024-00873-6","DOIUrl":"https://doi.org/10.1007/s11587-024-00873-6","url":null,"abstract":"<p>Let <i>G</i> be a finite group. A group <i>G</i> is called a <i>T</i> group if its every subnormal subgroup is normal. A subgroup <i>H</i> of <i>G</i> is called Hall normally embedded in <i>G</i> if <i>H</i> is a Hall subgroup of <span>(H^G)</span>, where <span>(H^G)</span> is the normal closure of <i>H</i> in <i>G</i>. Using the notion of Hall normally embedded subgroups, we characterize supersolvable groups and solvable <i>T</i>-group. First, we prove that if every cyclic subgroup of <i>G</i> of order prime or 4 is Hall normally embedded in <i>G</i>, then <i>G</i> is supersolvable with a well defined structure. Second, we prove that an <i>A</i>-group <i>G</i> is supersolvable if and only if its Sylow subgroups are products of cyclic Hall normally embedded subgroups of <i>G</i>. Final, we show that <i>G</i> is a solvable <i>T</i>-group if and only if every <i>p</i>-subgroup of <i>G</i> is Hall normally embedded in <i>G</i>, for all primes <span>(pin pi (G))</span>.</p>","PeriodicalId":21373,"journal":{"name":"Ricerche di Matematica","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2024-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141550259","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}
Pub Date : 2024-06-29DOI: 10.1007/s11587-024-00870-9
Nasrin Dastborhan, Hamid Mousavi
Let ({mathfrak {Nil}}) be the class of nilpotent groups and G be a group. We call G a meta-({mathfrak {Nil}})-Hamiltonian group if any of its non-({mathfrak {Nil}}) subgroups is normal. Also, we call G a para-({mathfrak {Nil}})-Hamiltonian group if G is a non-({mathfrak {Nil}}) group and every non-normal subgroup of G is either a ({mathfrak {Nil}})-group or a minimal non-({mathfrak {Nil}}) group. In this paper we investigate the class of finitely generated meta-({mathfrak {Nil}})-Hamiltonian and para-({mathfrak {Nil}})-Hamiltonian groups.
设 ({mathfrak {Nil}}) 是零能群的类,G 是一个群。如果 G 的任何一个非({mathfrak {Nil}})子群都是正则群,我们就称 G 为元({mathfrak {Nil}})-哈密尔顿群。另外,如果 G 是一个非({mathfrak {Nil}})群,并且 G 的每个非正常子群要么是一个 ({mathfrak {Nil}})群,要么是一个最小的非({mathfrak {Nil}})群,那么我们称 G 为准({mathfrak {Nil}})-哈密尔顿群。本文将研究有限生成的元({mathfrak {Nil}})-哈密尔顿群和准({mathfrak {Nil}})-哈密尔顿群。
{"title":"Groups whose non-normal subgroups are either nilpotent or minimal non-nilpotent","authors":"Nasrin Dastborhan, Hamid Mousavi","doi":"10.1007/s11587-024-00870-9","DOIUrl":"https://doi.org/10.1007/s11587-024-00870-9","url":null,"abstract":"<p>Let <span>({mathfrak {Nil}})</span> be the class of nilpotent groups and <i>G</i> be a group. We call <i>G</i> a meta-<span>({mathfrak {Nil}})</span>-Hamiltonian group if any of its non-<span>({mathfrak {Nil}})</span> subgroups is normal. Also, we call <i>G</i> a para-<span>({mathfrak {Nil}})</span>-Hamiltonian group if <i>G</i> is a non-<span>({mathfrak {Nil}})</span> group and every non-normal subgroup of <i>G</i> is either a <span>({mathfrak {Nil}})</span>-group or a minimal non-<span>({mathfrak {Nil}})</span> group. In this paper we investigate the class of finitely generated meta-<span>({mathfrak {Nil}})</span>-Hamiltonian and para-<span>({mathfrak {Nil}})</span>-Hamiltonian groups.</p>","PeriodicalId":21373,"journal":{"name":"Ricerche di Matematica","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2024-06-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141503420","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}
Pub Date : 2024-05-19DOI: 10.1007/s11587-024-00869-2
M. Irshad, K. Archana, R. Maya, S. Nadarajah
{"title":"On extropy properties of record ranked set sampling","authors":"M. Irshad, K. Archana, R. Maya, S. Nadarajah","doi":"10.1007/s11587-024-00869-2","DOIUrl":"https://doi.org/10.1007/s11587-024-00869-2","url":null,"abstract":"","PeriodicalId":21373,"journal":{"name":"Ricerche di Matematica","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2024-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141124335","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}
Pub Date : 2024-05-16DOI: 10.1007/s11587-024-00868-3
S. M. Sheikholeslami, H. Shooshtari
{"title":"On the harmonic index and algebraic connectivity","authors":"S. M. Sheikholeslami, H. Shooshtari","doi":"10.1007/s11587-024-00868-3","DOIUrl":"https://doi.org/10.1007/s11587-024-00868-3","url":null,"abstract":"","PeriodicalId":21373,"journal":{"name":"Ricerche di Matematica","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2024-05-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140970581","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}
Pub Date : 2024-05-13DOI: 10.1007/s11587-024-00867-4
Hongbing Ju, Feng Wang, Hongguang Wu
Martingale optimal transportation has gained significant attention in mathematical finance due to its applications in pricing and hedging. A key distinguishing factor between martingale optimal transportation and traditional optimal transportation is the concept of a peacock, which refers to a sequence of measures satisfying the convex order property. In the realm of traditional optimal transportation, the Wasserstein geometry, induced by a transportation problem with the p-th power of distance as the cost, provides valuable geometric insights. This motivates us to investigate the differences between Wasserstein geometries with and without the martingale constraint. As a first step, this paper focuses on studying the topological properties of convex order, with the aim of establishing a foundational understanding for further exploration of the geometric properties of martingale Wasserstein geometry.
由于在定价和套期保值中的应用,马氏最优运输在数学金融学中获得了极大的关注。马丁格尔最优运输与传统最优运输之间的一个关键区别因素是孔雀概念,孔雀是指满足凸序特性的计量序列。在传统最优运输领域,以距离的 p 次幂为成本的运输问题所引发的瓦瑟斯坦几何提供了宝贵的几何见解。这促使我们研究有马丁格尔约束和无马丁格尔约束的瓦瑟斯坦几何之间的差异。作为第一步,本文重点研究凸序的拓扑特性,目的是为进一步探索马氏瓦瑟斯坦几何的几何特性奠定基础。
{"title":"Topological properties of convex order in Wasserstein metric spaces","authors":"Hongbing Ju, Feng Wang, Hongguang Wu","doi":"10.1007/s11587-024-00867-4","DOIUrl":"https://doi.org/10.1007/s11587-024-00867-4","url":null,"abstract":"<p>Martingale optimal transportation has gained significant attention in mathematical finance due to its applications in pricing and hedging. A key distinguishing factor between martingale optimal transportation and traditional optimal transportation is the concept of a peacock, which refers to a sequence of measures satisfying the convex order property. In the realm of traditional optimal transportation, the Wasserstein geometry, induced by a transportation problem with the <i>p</i>-th power of distance as the cost, provides valuable geometric insights. This motivates us to investigate the differences between Wasserstein geometries with and without the martingale constraint. As a first step, this paper focuses on studying the topological properties of convex order, with the aim of establishing a foundational understanding for further exploration of the geometric properties of martingale Wasserstein geometry.</p>","PeriodicalId":21373,"journal":{"name":"Ricerche di Matematica","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2024-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140930389","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}