On Invariants of Virtual Links

We propose a new method of generalizing classical link invariants for the case of virtual links. In particular, we have generalized the knot quandle, the knot fundamental group, the Alexander module, and the coloring invariants. The virtual Alexander module leads to a definition of VA-polynomial that has no analogue in the classical case (i.e. vanishes on classical links).     

Conway Polynomial and Oriented Rotant Links

We prove that the Conway polynomial of oriented links is not changed by the rotation operation of Anstee, Przytycki and Rolfsen.Mathematics Subject Classifications (2000). 57M25, 57M27Supported by KBN grant No 2P03A00218     

整系数多项式因式分解的一种新方法

利用整系数多项式与正有理数的对应 ,将多项式因式分解通过对真分数序列筛选的办法求得因式 ,给出了整系数多项式因式分解的一种新方法 .     

一类基函数的构造问题

对文[1]中给出的基函数作了改进,改进后的基函数不仅形式简单,而且具有良好的几何性质.然后引进多项式树的概念,从更广泛意义出发讨论了一类基函数的构造问题.给基函数的构造提供了一个直观的途径.     

某些三维流形不变量的计算

Ｔｈｅｃａｌｃｕａｌｔｉｏｎｏｆ〈ｚｋ１,ｚｋ２,…,ｚｋｎ〉ＬｏｆｔｈｉｓｐａｐｅｒｗｉｌｌｂｅｉｎｔｅｒｍｏｆｔｈｅＫａｕｆｆｍａｎｂｒａｃｋｅｔ－ｐｏｌｙｎｏｍｉａｌ［１,２,３］．ＴｈｅＫａｕｆｆｍａｎｂｒａｃｋｅｔｐｏｌｙｎｏｍｉａｌｏｆａｐｌａｎａｒｄｉａｇｒａｍｏｆａｎｕｎｏｒｉｅｎｔｅｄｌｉｎｋｉｓａｎｅｌｅｍｅｎｔ〈Ｄ〉∈Ｚ［Ａ,Ａ－１］ｄｅｆｉｎｅｄｂｙｔｈｅｆｏｌｌｏｗｉｎｇｐｒｏｃｅｓｓ．ＡｓｔａｔｅｏｆＤｉｓｄｅｆｉｎｅｄｔｏｂｅａｍａｐｓｆｒｏｍｔｈｅｃｒｏｓｓｉｎｇ…     

Zeros Distribution of the Jones Polynomial for Pretzel Links

In this paper, we deal with basic properties of some pretzel links and properties of the Jones polynomials of some pretzel links. By using these properties, the zero distribution of pretzel links is st...     

State Model and the Link Polynomial with Two Variables

State representation is used to discuss the link with two variables, and the estimation of breadth of the two variables(say l and m) is given for 5-links.     

一类整系数多项式在整数环上不可约性的判定

本文通过对整系数多项式系数的讨论，得到了关于一类次数大于五的整系数多项式在整数环上是否可约的一个判别法。     

Polynomial Invariants of Knots and Links

The class of knots corresponding to d-diagrams with m vertical and n horizontal chords is considered and the set of their invariant polynomials is calculated. Bibliography: 2 titles.     

Polynomial and Regular Maps into Grassmannians

We find a regular deformation retraction _n,r (K): Idem _n,r (K) G _n,r (K) from the manifold Idem _n,r (K) of idempotent n × n matrices with rank r to the Grassmannian manifold G _n,r (K) over K the reals, complex numbers or quaternions. Then we derive an injection from the sets of homotopy classes of complex-valued polynomial to such a set of real-valued regular maps, where denotes the Zariski closure in the affine space ⁿ of a subset ⁿ . Furthermore, we list complex-valued polynomial maps ^{2 2} of any Brouwer degree and deduce that the map ()_2,1: Idem()_2,1 G()_2,1 yields an isomorphism [ ² ] [ ², ²] of cyclic infinite homotopy groups. Finally, we show that every nonzero even Brouwer degree of the spheres ⁿ and ⁿ cannot be realized by a real-valued (resp. complex-valued) homogeneous polynomial map provided that n is even.     

Extrema of a Real Polynomial

In this paper, we investigate critical point and extrema structure of a multivariate real polynomial. We classify critical surfaces of a real polynomial f into three classes: repeated, intersected and primal critical surfaces. These different critical surfaces are defined by some essential factors of f, where an essential factor of f means a polynomial factor of f–c ₀, for some constant c ₀. We show that the degree sum of repeated critical surfaces is at most d–1, where d is the degree of f. When a real polynomial f has only two variables, we give the minimum upper bound for the number of other isolated critical points even when there are nondegenerate critical curves, and the minimum upper bound of isolated local extrema even when there are saddle curves. We show that a normal polynomial has no odd degree essential factors, and all of its even degree essential factors are normal polynomials, up to a sign change. We show that if a normal quartic polynomial f has a normal quadratic essential factor, a global minimum of f can be either easily found, or located within the interior(s) of one or two ellipsoids. We also show that a normal quartic polynomial can have at most one local maximum.     

Polynomial Invariants of Special Groups Generated by Reflections

Generators are obtained for the ring of invariants of the group H created by reflections and which satisfy the following condition: the H-orbits of the directions of symmetry of this group are infinite and their linear shells form a triplet of planes with pairwise zero intersections. Conditions are identified such that the ring of invariants of the group H is not free.     

矩阵多项式的逆矩阵的求法

给出了矩阵多项式的逆矩阵的一般求法.     

Contraction–Deletion Invariants for Graphs

We consider generalizations of the Tutte polynomial on multigraphs obtained by keeping the main recurrence relation T(G)=T(G/e)+T(G−e) for eE(G) neither a bridge nor a loop and dropping the relations for bridges and loops. Our first aim is to find the universal invariant satisfying these conditions, from which all others may be obtained. Surprisingly, this turns out to be the universal V-function Z of Tutte (1947, Proc. Cambridge Philos. Soc.43, 26–40) defined to obey the same relation for bridges as well. We also obtain a corresponding result for graphs with colours on the edges and describe the universal coloured V-function, which is more complicated than Z. Extending results of Tutte (1974, J. Combin. Theory Ser. B16, 168–174) and Brylawski (1981, J. Combin. Theory Ser. B30, 233–246), we give a simple proof that there are non-isomorphic graphs of arbitrarily high connectivity with the same Tutte polynomial and the same value of Z. We conjecture that almost all graphs are determined by their chromatic or Tutte polynomials and provide mild evidence to support this.     

Polynomial Reproduction in Subdivision

We study conditions on the matrix mask of a vector subdivision scheme ensuring that certain polynomial input vectors yield polynomial output again. The conditions are in terms of a recurrence formula for the vectors which determine the structure of polynomial input with this property. From this recurrence, we obtain an algorithm to determine polynomial input of maximal degree. The algorithm can be used in the design of masks to achieve a high order of polynomial reproduction.     

The polynomial invariants of twisted links

A twisted link is a generalization of a virtual link, which is related to a link diagram on a closed, possibly non-orientable surface. In this paper we generalize the Miyazawa polynomial invariant of a virtual link to an invariant of a twisted link in two formulae one of which is introduced by A. Ishii and the other by the author.     

零化多项式的一个应用

利用矩阵的零化多项式 ,给出计算标准基解矩阵 e At的一个公式 .利用向量关于矩阵的零化多项式 ,给出常系数齐次线性微分方程组初值问题的一个求解公式 .相应地 ,可以推出常系数齐次线性差分方程组在给定的初始条件下的一个求解公式 .     

Invariants of Composite Networks Arising as a Tensor Product

We generalize Brylawski’s formula of the Tutte polynomial of a tensor product of matroids to colored connected graphs, matroids, and disconnected graphs. Unlike the non-colored tensor product where all edges have to be replaced by the same graph, our colored generalization of the tensor product operation allows individual edge replacement. The colored Tutte polynomials we compute exists by the results of Bollobás and Riordan. The proof depends on finding the correct generalization of the two components of the pointed Tutte polynomial, first studied by Brylawski and Oxley, and on careful enumeration of the connected components in a tensor product. Our results make the calculation of certain invariants of many composite networks easier, provided that the invariants are obtained from the colored Tutte polynomials via substitution and the composite networks are represented as tensor products of colored graphs. In particular, our method can be used to calculate (with relative ease) the expected number of connected components after an accident hits a composite network in which some major links are identical subnetworks in themselves.