Forbidden Subgraphs, Distance,and Hamiltonicity

ＦｏｒｂｉｄｄｅｎＳｕｂｇｒａｐｈｓ，Ｄｉｓｔａｎｃｅ，ａｎｄＨａｍｉｌｔｏｎｉｃｉｔｙＨＵＺｈｉｑｕａｎＤｅｐａｒｔｍｅｎｔｏｆＭａｔｈｅｍａｔｉｃｓ，ＨｕａｚｈｏｎｇＮｏｒｍａｌＵｎｉｖｅｒｓｉｔｙ，Ｗｕｈａｎ４３００７０Ａｂｓｔｒａｃｔ：Ａｇｒ...     

Two Sufficient Conditions for Hamiltonian Graphs

ＴｗｏＳｕｆｆｉｃｉｅｎｔＣｏｎｄｉｔｉｏｎｓｆｏｒＨａｍｉｌｔｏｎｉａｎＧｒａｐｈｓＬＩＧｕｏｊｕｎ（ＤｅｐａｒｔｍｅｎｔｏｆＭａｔｈｅｍａｔｉｃｓ，ＹａｎｔａｉＴｅａｃｈｅｒ＇ｓＣｏｌｌｅｇｅ，Ｙａｎｔａｉ２６４０００，Ｓｈａｎｄｏｎｇ）ＬＩＵＺ...     

A DEGREE CONDITION FOR THE EXISTENCE OF CONNECTED [k, k 1]-FACTORS

ＡＤＥＧＲＥＥＣＯＮＤＩＴＩＯＮＦＯＲＴＨＥＥＸＩＳＴＥＮＣＥＯＦＣＯＮＮＥＣＴＥＤ［ｋ，ｋ＋１］－ＦＡＣＴＯＲＳＡＤＥＧＲＥＥＣＯＮＤＩＴＩＯＮＦＯＲＴＨＥＥＸＩＳＴＥＮＣＥＯＦＣＯＮＮＥＣＴＥＤ［ｋ，ｋ＋１］－ＦＡＣＴＯＲＳ￥ＣＡＩＭａｏｃｈｅｎ...     

PANCONNECTIVITY AND 2-CONNECTED CLAW-FREE GRAPHS

ＰＡＮＣＯＮＮＥＣＴＩＶＩＴＹＡＮＤ２－ＣＯＮＮＥＣＴＥＤＣＬＡＷ－ＦＲＥＥＧＲＡＰＨＳ￥ＧＡＯＪｉｎｇｚｈｅｎ（ＤｅｐａｒｔｍｅｎｔｏｆＭａｔｈｅｍａｔｉｃｓ，ＳｈａｄｄｏｃｋＮｏｒｍａｌＵｎｉｖｅｒｓｉｔｙ，Ｊｉｎａｎ２５００１４，Ｃｈｉｎａ）Ｚ...     

TREE DECOMPOSITIONS OF MULTIGRAPHS

1.IntroductionInthispaperweconsideronlyfiniteundirectedlooplessgraphs.ForasubgraphHofG,E(H)andP(H)denotethenumberofedgesandthenUmberofcyclesinHrespectively.GiventwodisjointsubsetsXandYofV(G),wewriteEG(X,Y)={acEE(G)IxEX,y6Y}.IfTisatreeinGande=acEG--E(T)with{u,v}CV(T),thenT econtainsauniquecycle.WedenotethiscyclebyC(T,e).Aforestiscalledak-tree-forestifitconsistsofexactlykpairwisedisjointtrees.ForagraphG,ifE(G)canbepartitionedilltoseveralpairwisedisjointsetsas{EI,EZ,...,EI}such…     

GRAPHS WHOSE CIRCULAR CLIQUE NUMBER EQUAL THE CLIQUE NUMBER

The circular clique number of a graph G is the maximum fractional k/d such that G^kd admits a homomorphism to G. In this paper, we give some sufficient conditions for graphs whose circular clique number equal the clique number, we also characterize the K1,3-free graphs and planar graphs with the desired property.     

A NEIGHBORHOOD UNION CONDITION FOR PANCYCLIC GRAPHS

1.IntroductionWeconsideronlysimplefinitegraphs.OurbasicnotationandterminologynotdefinedherefollowthOSeofBondyandMurtyll].ForagraphG,letV(G)andE(G)(orjustVandE)deDOtelievertexsetandedgeset,respectively.Wedenoteapathandacyclecontaining8veniCesbyPaandCarespectively.ThecycleCaiscalledans-cycle.Denotebyg(G)(orbrieflybyg)thegirthofG1.SetNC=min{IN(u)UN(v)l:tv相似文献   

Quantum Algorithm for Boolean Equation Solving and Quantum Algebraic Attack on Cryptosystems

Journal of Systems Science and Complexity - This paper presents a quantum algorithm to decide whether a Boolean equation system $$\mathcal{F}$$ has a solution and to compute one if $$\mathcal{F}$$...     

连通、几乎局部连通无爪图是完全圈可扩的

设Ｇ是一个图,Ｂ ＝ ｛ｖ ∈Ｖ（Ｇ）｜〈Ｎ（ｖ）〉不连通｝．如果Ｂ是独立集,并且ｖ ∈Ｂ,ｕ ∈Ｖ（Ｇ）, 使〈Ｎ（ｕ） ∪｛ｕ｝〉连通,则称Ｇ是几乎局部连通图．本文证明：连通、几乎局部连通无爪图是完全圈可扩的．     

Some semi-bent functions with polynomial trace form

This paper is devoted to the study of semi-bent functions with several parameters flexible on the finite field F2n.Boolean functions defined on F2n of the form f（r）ab（x） =Trn1（axr（2m-1））＋Tr41（bx（2n-1）/5） and the form g（rs）abcd（x）=Trn1（axr（2m-1））＋Tr41（bx（2n-1）/5）＋Trn1（cx（2m-1）1/2＋1）＋Trn1（dx（2m-1）s＋1） where n = 2m,m = 2（mod 4）,a,c ∈ F2n,and b ∈ F（16）,d ∈ F2,are investigated in constructing new classes of semi-bent functions.Some characteristic sums such as Kloosterman sums and Weil sums are employed to determine whether the above functions are semi-bent or not.     

A MacWilliams type identity on Lee weight for linear codes over \mathbb{F}_2 + u\mathbb{F}_2^*

In this paper,the MacWilliams type identity for the m-ply Lee weight enumerator for linear codes over F₂ + uF₂ is determined.As an application of this identity,the authors obtain a MacWilliams type identity on Lee weight for linear codes over F_2^m+ uF_2^m.Furthermore,the authors prove a duality for the m-ply Lee weight distributions by taking advantage of the Krawtchouk polynomials.     

Good p-ary quasic-cyclic codes from cyclic codes over $$\mathbb{F}_ p + v\mathbb{F}_ p$$

This paper introduces a Gray map from（F_p + uF_p）ⁿ to F_p²ⁿ,and describes the relationship between codes over F_p + vF_p and their Gray images.The authors prove that every cyclic code of arbitrary length n over F_p + vF_p is principal,and determine its generator polynomial as well as the number of cyclic codes.Moreover,the authors obtain many best-known p-ary quasic-cyclic codes in terms of their parameters via the Gray map.     

爪心独立图的可扩圈

图Ｇ中的一个与Ｋ１，３同构的导出子图叫做Ｇ的一个爪。爪中的３次顶点叫该爪的爪心。Ｂ表示Ｇ中所有爪心构成的集合。本文将证明：设Ｇ是顶点数≥３的连通、局部连通图，如果Ｇ的爪心集合Ｂ是点独立集，且Ｇ－Ｂ是局部连通的，则Ｇ是完全圈可扩的。     

THE NORMALITY OF CAYLEY GRAPHS OF SIMPLE GROUP A_5 WITH SMALL VALENCIES

1.IntroductionLetGbeafinitegroup.ForaCayleysubsetSofGnotcontainingtheidentityelement1,theCayley(di)graphX~Cay(G,S)ofGwithrespecttoSisdefinedasthedirectedgraphwithvertexsetV(X)=GandedgesetE(X)={(g,sg)IgEG,s6S}.IfS=S--',thentheadjacencyrelationissymmet...     

THE ASCENDING SUBGRAPH DECOMPOSITION OF K_n-H_(2n-1)

1.IntroductiollAlavi,Y.etal.presentedaconceptofsubgraphdecompositionin[1],whichiscalledascendingsubgraphdecomposition(abbreviatedASD).GivenagraphGwithqedges,C: ,5q5C: ,GissaidtohaveanASD,ifthereisnsuchthatGcanbedecomposedintonsubgraphsGIjGi,''3G.withouti…     

LONG DOMINATING CYCLES IN GRAPHS

1.IntroductionAllgraphsconsideredinthispaperwillbefiniteandsimple.WeuseBondyandMurty[1]forterminologyandnotationsnotdefinedhere.LetG=(V,E)beagraphofordernandCbeacycleinG.Ciscalledadominatingcycle,orbrieflyaD--cycle,ifV(G)\V(C)isanindependentsetinG.ForavertexvinG,theneighborhoodofvisdenotedbyN(v),andthedegreeofvisdenotedbyd(v).FortwosubsetsSandTofV(G),wesetNT(S)~{vET\S:N(v)nS/0}.WewriteN(u,v)insteadofNV(G)({u,v})foranyu,vEV(G).IfFandHaretwosubgraphsofG,wealsowriteNF(H)insteado…     

A general iterative method of fixed points for equilibrium problems and optimization problems

The purpose of this paper is to present a general iterative scheme as below:

ENDOMORPHISMS OF LIE ALGEBRA F[t]d／dt

Let F be a field of characteristic zero. W_n =is the Witt algebra over F, W_n~ =is Lie subalgebra of W_n. It is well known both W_n and W_n~ are simple infinite dimensional Lie algebra. In Zhao's paper, it was conjectured thatEnd(W_n~ ) - {0} = Aut(W_n~ ) and it was proved that the validity of this conjecture im-plies the validity of the well-known Jacobian conjecture. In this short note, we check theconjecture above for n = 1. We show End(W_1~ ) - {0} = Aut(W_1~ ).     

On the Laplacian spectral radii of trees with nearly perfect matchings

Let be the set of trees on 2k+1 vertices with nearly perfect matchings, and let be the set of trees on 2k + 2 vertices with perfect matchings. The largest Laplacian spectral radii of trees in and and the corresponding trees were given by Guo (2003). In this paper, the authors determine the second to the sixth largest Laplacian spectral radii among all trees in and give the corresponding trees. This research is supported by the National Natural Science Foundation of China under Grant No. 10331020.     

Removable ears of 1-extendable graphs

<正> Carvalho,Lucchesi and Murty proved that any 1-extendable graph G different from K_2and C_(2n)has at least Δ(G)edge-disjoint removable ears,and any brick G distinct from K_4 and■hasat least Δ(G)-2 removable edges,where Δ(G)denotes the maximum degree of G.In this paper,weimprove the lower bounds for numbers of removable ears and removable edges of 1-extendable graphs.It is proved that any 1-extendable graph G different from K_2 and C_(2n)has at least χ′(G)edge-disjointremovable ears,and any brick G distinct from K_4 and■has at least χ′(G)-2 removable edges,whereχ′(G)denotes the edge-chromatic number of G.