Báo cáo toán học: " The tau constant of a metrized graph and its behavior under graph operations" ppsx

... that the lower bound to the tau constant of a banana graph Γ is ℓ(Γ) 16 . For a banana graph Γ, a participant in the REU at UGA, Crystal Gordon, found by applying Lagrange multipliers that the ... Cinkir, The t au constant and the edge connectivity of a metrized graph, submitted. Available at http://arxiv.org/abs/0901.14 81 [5] Z. Cinkir, The tau co...

Ngày tải lên: 08/08/2014, 14:23

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Ngày tải lên: 05/08/2014, 10:20

... that the translational hull of a type -A semigroup is still of the same type [6], it is natural to ask whether the translational hull of C-Ehresmann semigroups and their generalized classes are ... itself a right translation of S if (ab)ρ = a( bρ) for all a, b ∈ S. A left translation λ and a right translation ρ of S are said to be linked if a( λb)= (a )b for al...

Ngày tải lên: 06/08/2014, 05:20

... is a kind of generalization of gener- alized Taft algebra and of course Taft algebra. Therefore, it is natural to ask the following question: whether is the quantum double of dual Andruskiewitsch- Schneider ... similarly.  By [11], we know that the most typical examples of basic Hopf algebras of finite representation type are Taft algebras and the dual of A( n, d,...

Ngày tải lên: 06/08/2014, 05:20

... subgraphs of G is known as its deck. The characteristic polynomial of G is the characteristic polynomial of its adjacency matrix A and is defined by P G (x)=det(xI − A) . We call the collection of ... Eigenspaces of graphs. Encyclopedia of Mathematics and its Applications, 66. Cambridge University Press, Cambridge, 1997. [4] N. Deo, F. Harary and A. J. Schwenk...

Ngày tải lên: 07/08/2014, 06:20

... Stegun, Handbook of Mathematical Functions,NationalBureauof Standards, Washington DC, 1972. 2. P. Erd˝os and P. Tur´an, On some problems of a statistical group theory, III,, Acta Math. Acad. Sci. ... is an explicit constant defined below. Our argument shares some similarities with that of [4], but is more elementary and permits a more explicit 1991 Mathematics Subject Classifica...

Ngày tải lên: 07/08/2014, 06:22

... of Mathematical Sciences State University of New York Binghamton, NY 13902–6000, USA matthias@math.binghamton.edu Ira M. Gessel ∗ Department of Mathematics Brandeis University Waltham, MA 02454–9110, ... j>1, and (3) follows from (5) and (6). ✷ Remark. It is possible to avoid the use of complex analysis and give a purely formal power series proof of the theorem. We in...

Ngày tải lên: 07/08/2014, 06:22

... arcs of a circle such that adjacent vertices are mapped to intersecting arcs. The width ofsucharepresentationisthemaximumnumberofarcshavingapointincommon. The arc-width(aw) of a graph is the minimum ... combinatorics 8 (2001), #R34 4 The arc-width of a graph J ´ anos Bar ´ at ∗ jbarat@math.u-szeged.hu and P ´ eter Hajnal † hajnal@math.u-szeged.hu Bolyai Institute Uni...

Ngày tải lên: 07/08/2014, 06:22

... B 0 =0andA 1 =1 for all s, t ∈ >0 .DenotingA =  ∞ i=1 A i and B =  ∞ i=1 B i ,wehaveA ∪ B = >0 ,and A ∩ B = ∅. Fraenkel [9] generalized the classical Wythoff game (s = t =1)tothecases =1,t≥ 1, and showed ... complexity of the characteristic function of A. Forfixed s, t ∈ >0 , define the characteristic function of A as χ = χ (A) : >0 −→ {0, 1},where χ(x)= ...

Ngày tải lên: 07/08/2014, 06:23

... Japan ohsugi@rkmath.rikkyo.ac.jp Takayuki Hibi Department of Pure and Applied Mathematics Graduate School of Information Science and Technology Osaka University Toyonaka, Osaka 560-0043, Japan hibi@math.sci.osaka-u.ac.jp Submitted: ... is Gorenstein. Then the h-vector of K[P] is unimodal. References [1] C. A. Athanasiadis, Ehrhart polynomials, simplicial polytopes, magic squares...

Ngày tải lên: 07/08/2014, 08:22