Pub Date : 2022-12-15DOI: 10.21136/mb.2022.0045-22
S. Padhi, J. Graef
. We study the existence of positive solutions to the fourth-order two-point boundary value problem
.我们研究了四阶两点边值问题正解的存在性
{"title":"Positive solutions of a fourth-order differential equation with integral boundary conditions","authors":"S. Padhi, J. Graef","doi":"10.21136/mb.2022.0045-22","DOIUrl":"https://doi.org/10.21136/mb.2022.0045-22","url":null,"abstract":". We study the existence of positive solutions to the fourth-order two-point boundary value problem","PeriodicalId":45392,"journal":{"name":"Mathematica Bohemica","volume":null,"pages":null},"PeriodicalIF":0.5,"publicationDate":"2022-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47718327","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-12-06DOI: 10.21136/mb.2022.0152-21
Rabah Mecheter, F. Mokhtari
. In this paper, we study the existence results for some parabolic equations with degenerate coercivity, singular lower order term depending on the gradient, and positive initial data in L 1 .
． 本文研究了一类具有退化矫顽力、奇异低阶项依赖于梯度、初始数据为正的抛物方程的存在性结果。
{"title":"Existence results for some nonlinear parabolic equations with degenerate coercivity and singular lower-order terms","authors":"Rabah Mecheter, F. Mokhtari","doi":"10.21136/mb.2022.0152-21","DOIUrl":"https://doi.org/10.21136/mb.2022.0152-21","url":null,"abstract":". In this paper, we study the existence results for some parabolic equations with degenerate coercivity, singular lower order term depending on the gradient, and positive initial data in L 1 .","PeriodicalId":45392,"journal":{"name":"Mathematica Bohemica","volume":null,"pages":null},"PeriodicalIF":0.5,"publicationDate":"2022-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47400855","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-12-05DOI: 10.21136/mb.2022.0122-21
NoorA’lawiah Abd Aziz, Nader Jafari Rad, H. Kamarulhaili
. Let G be a 3-connected triangulated disc of order n with the boundary cycle C of the outer face of G . Tokunaga (2013) conjectured that G has a dominating set of cardinality at most 14 ( n +2). This conjecture is proved in Tokunaga (2020) for G − C being a tree. In this paper we prove the above conjecture for G − C being a unicyclic graph. We also deduce some bounds for the double domination number, total domination number and double total domination number in triangulated discs.
{"title":"On the domination of triangulated discs","authors":"NoorA’lawiah Abd Aziz, Nader Jafari Rad, H. Kamarulhaili","doi":"10.21136/mb.2022.0122-21","DOIUrl":"https://doi.org/10.21136/mb.2022.0122-21","url":null,"abstract":". Let G be a 3-connected triangulated disc of order n with the boundary cycle C of the outer face of G . Tokunaga (2013) conjectured that G has a dominating set of cardinality at most 14 ( n +2). This conjecture is proved in Tokunaga (2020) for G − C being a tree. In this paper we prove the above conjecture for G − C being a unicyclic graph. We also deduce some bounds for the double domination number, total domination number and double total domination number in triangulated discs.","PeriodicalId":45392,"journal":{"name":"Mathematica Bohemica","volume":null,"pages":null},"PeriodicalIF":0.5,"publicationDate":"2022-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45498339","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-10-17DOI: 10.21136/mb.2022.0029-22
Vandana P. Bhamre, Madhukar. M. Pawar
. The concept of covering energy of a poset is known and its McClelland type bounds are available in the literature. In this paper, we establish formulas for the covering energy of a crown with 2 n elements and a fence with n elements. A lower bound for the largest eigenvalue of a poset is established. Using this lower bound, we improve the McClelland type bounds for the covering energy for some special classes of posets.
{"title":"Covering energy of posets and its bounds","authors":"Vandana P. Bhamre, Madhukar. M. Pawar","doi":"10.21136/mb.2022.0029-22","DOIUrl":"https://doi.org/10.21136/mb.2022.0029-22","url":null,"abstract":". The concept of covering energy of a poset is known and its McClelland type bounds are available in the literature. In this paper, we establish formulas for the covering energy of a crown with 2 n elements and a fence with n elements. A lower bound for the largest eigenvalue of a poset is established. Using this lower bound, we improve the McClelland type bounds for the covering energy for some special classes of posets.","PeriodicalId":45392,"journal":{"name":"Mathematica Bohemica","volume":null,"pages":null},"PeriodicalIF":0.5,"publicationDate":"2022-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44375693","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-10-11DOI: 10.21136/mb.2022.0155-21
Cyril Gavala, M. Ploščica, Ivana Varga
{"title":"Congruence preserving operations on the ring $mathbb{Z}_{p^3}$","authors":"Cyril Gavala, M. Ploščica, Ivana Varga","doi":"10.21136/mb.2022.0155-21","DOIUrl":"https://doi.org/10.21136/mb.2022.0155-21","url":null,"abstract":"","PeriodicalId":45392,"journal":{"name":"Mathematica Bohemica","volume":null,"pages":null},"PeriodicalIF":0.5,"publicationDate":"2022-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42317582","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-09-29DOI: 10.21136/mb.2022.0033-22
Z. Şiar, R. Keskin, Elif Segah Öztas
. Let k > 2 and let ( P ( k ) n ) n > 2 − k be the k -generalized Pell sequence defined by P ( k ) n = 2 P ( k ) n − 1 + P ( k ) n − 2 + . . . + P ( k ) n − k for n > 2 with initial conditions In this study, we handle the equation P ( k ) n = y m in positive integers n , m , y , k such that k, y > 2 , and give an upper bound on n. Also, we will show that the equation P ( k ) n = y m with 2 6 y 6 1000 has only one solution given by P (2)7 = 13 2 .
． 让k n > 2,让(P (k)) k n > 2−be the k -generalized佩尔奈德fi序列n: P (k) = 2 (k) n−1 P + P (k) n−2。。P (k) + n (n−k for > 2与初始条件在这个研究,我们把手the equation P (k) n = y在积极integers n, m、y y这样的那个k, k > 2,和给上束缚在一个n .也会,我们会show that the equation P (k) n = m和y = 2 6 y 1000唯一溶液赐予了:P(2) 7 = 13。
{"title":"On perfect powers in $k$-generalized Pell sequence","authors":"Z. Şiar, R. Keskin, Elif Segah Öztas","doi":"10.21136/mb.2022.0033-22","DOIUrl":"https://doi.org/10.21136/mb.2022.0033-22","url":null,"abstract":". Let k > 2 and let ( P ( k ) n ) n > 2 − k be the k -generalized Pell sequence defined by P ( k ) n = 2 P ( k ) n − 1 + P ( k ) n − 2 + . . . + P ( k ) n − k for n > 2 with initial conditions In this study, we handle the equation P ( k ) n = y m in positive integers n , m , y , k such that k, y > 2 , and give an upper bound on n. Also, we will show that the equation P ( k ) n = y m with 2 6 y 6 1000 has only one solution given by P (2)7 = 13 2 .","PeriodicalId":45392,"journal":{"name":"Mathematica Bohemica","volume":null,"pages":null},"PeriodicalIF":0.5,"publicationDate":"2022-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42035013","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-09-08DOI: 10.21136/mb.2022.0187-21
B. Boudine
. A commutative ring R with unity is called a special principal ideal ring (SPIR) if it is a non integral principal ideal ring containing only one nonzero prime ideal, its length e is the index of nilpotency of its maximal ideal. In this paper, we show a characterization of irreducible polynomials over a SPIR of length 2. Then, we give a sufficient condition for a polynomial to be irreducible over a SPIR of any length e .
{"title":"Characterization of irreducible polynomials over a special principal ideal ring","authors":"B. Boudine","doi":"10.21136/mb.2022.0187-21","DOIUrl":"https://doi.org/10.21136/mb.2022.0187-21","url":null,"abstract":". A commutative ring R with unity is called a special principal ideal ring (SPIR) if it is a non integral principal ideal ring containing only one nonzero prime ideal, its length e is the index of nilpotency of its maximal ideal. In this paper, we show a characterization of irreducible polynomials over a SPIR of length 2. Then, we give a sufficient condition for a polynomial to be irreducible over a SPIR of any length e .","PeriodicalId":45392,"journal":{"name":"Mathematica Bohemica","volume":null,"pages":null},"PeriodicalIF":0.5,"publicationDate":"2022-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45469365","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-08-31DOI: 10.21136/mb.2022.0051-22
T. Dube
. Among completely regular locales, we characterize those that have the feature described in the title. They are, of course, localic analogues of what are called cl-isocompact spaces. They have been considered in T. Dube, I. Naidoo, C. N. Ncube (2014), so here we give new characterizations that do not appear in this reference.
{"title":"On locales whose countably compact sublocales have compact closure","authors":"T. Dube","doi":"10.21136/mb.2022.0051-22","DOIUrl":"https://doi.org/10.21136/mb.2022.0051-22","url":null,"abstract":". Among completely regular locales, we characterize those that have the feature described in the title. They are, of course, localic analogues of what are called cl-isocompact spaces. They have been considered in T. Dube, I. Naidoo, C. N. Ncube (2014), so here we give new characterizations that do not appear in this reference.","PeriodicalId":45392,"journal":{"name":"Mathematica Bohemica","volume":null,"pages":null},"PeriodicalIF":0.5,"publicationDate":"2022-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41594270","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-08-29DOI: 10.21136/mb.2022.0048-21
A. Tripathy
. In this work, necessary and sufficient conditions for the oscillation of solutions of 2-dimensional linear neutral delay difference systems of the form are established, where m > 0, α > 0, β > 0 are integers and a ( n ), b ( n ), c ( n ), d ( n ), p ( n ) are sequences of real numbers.
{"title":"Oscillation criteria for two dimensional linear neutral delay difference systems","authors":"A. Tripathy","doi":"10.21136/mb.2022.0048-21","DOIUrl":"https://doi.org/10.21136/mb.2022.0048-21","url":null,"abstract":". In this work, necessary and sufficient conditions for the oscillation of solutions of 2-dimensional linear neutral delay difference systems of the form are established, where m > 0, α > 0, β > 0 are integers and a ( n ), b ( n ), c ( n ), d ( n ), p ( n ) are sequences of real numbers.","PeriodicalId":45392,"journal":{"name":"Mathematica Bohemica","volume":null,"pages":null},"PeriodicalIF":0.5,"publicationDate":"2022-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48124282","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-08-29DOI: 10.21136/mb.2022.0157-21
J. Alzabut, S. Grace, A. Selvam, R. Janagaraj
. This paper aims at discussing asymptotic behaviour of nonoscillatory solutions of the forced fractional difference equations of the form where N 1 − γ = { 1 − γ, 2 − γ, 3 − γ, . . . } , 0 < γ 6 1, ∆ γ is a Caputo-like fractional difference operator. Three cases are investigated by using some salient features of discrete fractional calculus and mathematical inequalities. Examples are presented to illustrate the validity of the theoretical results.
{"title":"Nonoscillatory solutions of discrete fractional order equations\u0000 \u0000with positive and negative terms","authors":"J. Alzabut, S. Grace, A. Selvam, R. Janagaraj","doi":"10.21136/mb.2022.0157-21","DOIUrl":"https://doi.org/10.21136/mb.2022.0157-21","url":null,"abstract":". This paper aims at discussing asymptotic behaviour of nonoscillatory solutions of the forced fractional difference equations of the form where N 1 − γ = { 1 − γ, 2 − γ, 3 − γ, . . . } , 0 < γ 6 1, ∆ γ is a Caputo-like fractional difference operator. Three cases are investigated by using some salient features of discrete fractional calculus and mathematical inequalities. Examples are presented to illustrate the validity of the theoretical results.","PeriodicalId":45392,"journal":{"name":"Mathematica Bohemica","volume":null,"pages":null},"PeriodicalIF":0.5,"publicationDate":"2022-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43630341","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：