简介:At-hyperwheel(t≥3)oflengthl(orW(t)lforbrevity)isat-uniformhypergraph(V,E),whereE={e1,e2,...,el}andv1,v2,...,vlaredistinctverticesofV=∪eii=1lsuchthatfori=1,...,l,vi,vi+1∈eiandei∩ej=P,j∈/{i1,i,i+1},wheretheoperationonthesubscriptsismodulolandPisavertexofVwhichisdifferentfromvi,1≤i≤l.Inthispaper,theminimumcoveringproblemofMCλ(3,W(3)4,v)isinvestigated.DirectandrecursiveconstructionsonMCλ(3,W(3)4,v)arepresented.Thecoveringnumbercλ(3,W(3)4,v)isfinallydeterminedforanypositiveintegersv≥5andλ.
简介:ThechoicenumberofagraphG,denotedbyX1(G),istheminimumnumberksuchthatifalistofkcolorsisgiventoeachvertexofG,thereisavertexcoloringofGwhereeachvertexreceivesacolorfromitsownlistnomatterwhatthelistsare.Inthispaper,itisshowedthatX1(G)≤3foreachplanegraphofgirthnotlessthan4whichcontainsno6-,7-and9-cycles.
简介:Theobjectinthispaperistoconsidertheproblemofexistence,uniqueness,explicilrepresentationof(0,2)-interpolationonthezerosof(1-x2)Pn-1(x)/xwhennisodd,wherePn-1denotesLegendrepolynomialofdegreen-1,andtheproblemofconvergenceofinterpolatorypolynomials.
简介:WeuseMnforthesetofalln×nrealmatrices;(n)for{1,…,n};Snforthesymmetricgroupon〈n〉;A[α]α∈
简介:让Λ=kQ/I是有限维的Nakayama代数学,在Q是一个欧几里德几何学的图Yun徐舸电子邮件的地方:xuy@hubu.edu.cn参考书[1]。马克·莱恩,S.:相同,Grundlehren数学。Wiss。114,Springer,柏林,1975[2]。Happel,D.:有限维的代数学的Hochschildcohomology。在数学的讲课笔记,1404,108126(1989)[3]。Skowroński,A.:简单地连接的代数学和Hochschildcohomology。Proc。ICRAIV(渥太华,1992),能。数学。Soc。Proc,14,431447(1993)[4]。Assem,I.,delaPeña,J.A.:三角形的代数学的foundamental组。Comm。代数学,24,187208(1996)[5]。Gerstenhaber,M.:在戒指和代数学的变丑上。安。数学,79,59103(1964)[6]。Igusa,K.:笔记在上没有环推测。J。纯Appl。代数学,69,161176(1990)[7]。刘,S.X.,张,P.:截断的代数学的Hochschild相同。公牛。伦敦数学。Soc,26,427430(1994)[8]。Avramov,L.L.,Vigueé-Poirrier,M.:为光滑的Hochschild相同标准。Internat。数学。研究通知,1,1725(1992)[9]。汉,Y.:Hochschild(co)相同尺寸。J.伦敦数学。Soc,73(2),657668(2006)[10]。凯勒,B.:为DG代数学的周期的相同的不变性和本地化。J。纯Appl。代数学,123,223273(1998)[11]。Erdmann,K.,河边肥沃的低地T.:为班的self-injective代数学的扭曲的双性人模块和Hochschildcohomology一。论坛数学,11,177201(1999)[12]。Bardzell,M.J.,Locateli,A.C.,Marcos,E.N.:在截断的周期代数学的Hochschildcohomology上。CommAlg,28(3),16151639(2000)[13]。Assem,I.,Simson,D.,Skowroński,A.:联合代数学的表示理论的元素,伦敦数学。Soc。学生文章65,剑桥大学出版社,剑桥,2005[14]。Snashall,N.,Solberg,Ø.:支持变化和Hochschildcohomology
简介:<正>LetRbeanassociativeringnotnecessarilypossessinganidentityand(S,≤)astrictlytotallyorderedmonoidwhichisalsoartinianandsatisfiesthat0≤sforanys∈S.AssumethatMisaleftR-modulehavingproperty(F).ItisshownthatMisaco-HopfianleftR-moduleifandonlyif[MS,≤]isaco-Hopfanleft[[RS,≤]]-module.
简介:<正>Foranyintegersa1,a2,a3,a4andcwitha1a2a3a40(modp),thispapershowsthatthereexistsasolutionX=(x1,x2,x3,x4)∈Z4ofthecongruencea1x12+a2x22+a3x32+a4x42≡c(modp)suchthat‖X‖=max{|x1|,|x2|,|x3|,|x4|}《p1/2logp.
简介:Modelinglog-mortalityratesonO-UtypeprocessesandforecastinglifeexpectanciesareexploredusingU.S.data.IntheclassicLee-Cartermodelofmortality,thetimetrendandtheage-specificpatternofmortalityoveragegrouparelinear,thisisnotthefeatureofmortalitmodel.Toavoidthisdisadvantage,O-Utypeprocesseswillbeusedtomodelthelog-mortalityinthispaper.Infact,thismodelisanAR(1)process,butwithanonlineartimedriftterm.BasedonthemortalitydataofAmericafromHumanMortalitydatabase(HMD),mortalityprojectionconsistentlyindicatesapreferenceformortalitywithO-UtypeprocessesoverthosewiththeclassicalLee-Cartermodel.Bymeansofthismodel,thelowboundsofmortalityratesateveryagearegiven.Therefore,lengtheningofmaximumlifeexpectanciesspanisestimatedinthispaper.
简介:Itiswellknownthateveryprimeidealminimaloveraz-idealisalsoaz-ideal.TheconverseisalsowellknowninC(X).ThuswheneverIisanidealinC(X),thenI~(1/2)isaz-idealifandonlyifIis,inwhichcaseI~(1/2)=I.Weshowthesamefactforz~o-idealsandthenitturnsoutthatthesumofaprimaryidealandaz-ideal(z~o-ideal)inC(X)whicharenotinachainisaprimez-ideal(z~o-ideal).Wealsoshowthateverydecomposablez-ideal(z~o-ideal)inC(X)istheintersectionofafinitenumberofprimez-ideals(z~o-ideal).Somecounter-examplesingeneralringsandsomecharacterizationsforthelargest(smallest)z-idealandz~o-idealcontainedin(containing)anidealaregiven.
简介:让x:Mn是有非零主管弯曲的脐的免费hypersurface。然后,x与Laguerre公制的g被联系,Laguerre张肌\mathbbL\mathbb{L},Laguerre形式C,和一个Laguerre秒基础形成\mathbbB\mathbb{B}它是在Laguerre下面的x的invariants转变组。如果它的Laguerre形式消失,hypersurfacex被称为Laguerreisoparametric并且\mathbbB\mathbb的特征值{B}是不变的。在这份报纸,我们在4分类所有Laguerreisoparametrichypersurfaces。