Báo cáo toán học: "Distinguishing infinite graphs" ppt

... |G| ≤ .  We note that an infinite locally finite graph can have infinite distinguishing number. For a simple example consider the graph that is obtained from the one-way infinite path v 0 , v 1 , ... the infinite case and find many similarities. We also determine the distinguishing number of infinite hypercubes of arbitrary dimension. To this end we take recourse to elementary results abo...

Ngày tải lên: 07/08/2014, 15:22

... saying that there are graphs of arbitrarily large chromatic number with this property. Another infinite sequence of dense triangle-free graphs Stephan Brandt FB Mathematik & Informatik, WE ... the natural way to describe the structure of these graphs is in terms of graph homomorphisms. One infinite sequence of cores of dense maximal triangle-free graphs was known. All graphs in this seq...

Ngày tải lên: 07/08/2014, 06:22

... graphs. Motivated by a problem concerning accumulation points of infinite planar graphs, we generalize Tutte’s decomposition to include all infinite 2-connected graphs. 1 Introduction In [5], Tutte presents ... following problem concerning accumulation points of infinite graphs embedded in the plane provides motivation for generalizing Tutte’s decomposition to infinite graphs. Question 1...

Ngày tải lên: 07/08/2014, 08:20

... values in infinite families of k-crossing-critical graphs? We positively answer one half of his question in Theorem 3.1 and Proposition 2.1; • namely we construct, for all k > 2, infinite families ... (2003), 332–341. [11] G. Salazar, Infinite families of crossing-critical graphs with given average degree, Discrete Math. 271 (2003), 343–350. [12] J. ˇ Sir´aˇn, Infinite families of cros...

Ngày tải lên: 07/08/2014, 21:20

... An Infinite Family of Graphs with the Same Ihara Zeta Function Christo pher Storm Department of Mathematics ... Published: Jun 7, 2010 Mathematics Subject Classification: 05C38 Abstract In 2009, Cooper presented an infinite family of pairs of graphs which were con- jectured to have the same Ihara zeta function. ... pairs of graphs which share the same zeta function. 1. Introduction In 2009 ,...

Ngày tải lên: 08/08/2014, 12:22

... Describe a recursive construction for an infinite family of 2 - (2λ +2,λ+1,λ) designs. This construction has the property that if the initial design in the infinite family has the collection of five ... 2-designs has been determined for the cases λ =5,λ =6,andλ = 7. In this paper the existence of an infinite family of non-embeddable 2 - (2λ +2,λ +1,λ)designs,λ = 3(2 m ) − 1,m ≥ 1 is establi...

Ngày tải lên: 07/08/2014, 06:20

... were no infinite antichains in this partially ordered set, that would be surprising because, unlike the two partially ordered sets we mentioned in the first paragraph, P is defined over an infinite ... not contain an infinite antichain is a famous theorem of Robertson and Seymour [2, 3]). This is surprising too, as graphs are usually much more complex than permutations. 2 The infinite antic...

Ngày tải lên: 07/08/2014, 06:20

... 01, µ(1) = 10, and we extend it to infinite words by continuity. The infinite fixed point of µ beginning with 0 is denoted by t, hence t = 0110100110010110 ···. The infinite fixed point of µ beginning ... example x = 001011 = 00µ(1)11 = 0µ(00)1. 2. If x is an infinite overlap-free word on {0, 1}, then there exist u ∈{ε, 0, 1, 00, 11} and an infinite overlap-free word y on {0, 1} such that...

Ngày tải lên: 07/08/2014, 06:22

Ngày tải lên: 07/08/2014, 08:20

... V. Kumar, K. Yang, An infinite family of 3-designs from Preparata codes over Z 4 , Des. Codes Cryptogr. 15 (1998), no. 2, 175–181. [6] T. Helleseth, C. Rong, K. Yang, New infinite families of 3-designs ... Oh, Jangheon Oh and Hoseog Yu, New infinite families of 3-designs from algebraic curves over F q , European J. Combin. 28 (2007), no. 4, 1262–1269. [10] K. Ranto, Infinite families of 3...

Ngày tải lên: 07/08/2014, 15:22