Báo cáo toán học: "A new bound on the domination number of graphs with minimum degree two" docx

... X u )-DS of G. Hence, γ(G u ; X u ) ≤ |D v | + 1 = γ(G v ; X v ) + 1. ✷ the electronic journal of combinatorics 18 (2011), #P12 34 A new bound on the domination number of graphs with minimum degree ... is of interest to determine upper bounds on the domination number of a graph. In 1989, McCuaig and Shepherd [12] presented the beautiful result that t...

Ngày tải lên: 08/08/2014, 12:23

... (1) The second ingredient of our proof is the following result of Stiebitz. Lemma 3 ([5]) Let G be a k-critical graph containing at least one vertex of degree k − 1. Then the number of connected ... components of its high-vertex subgraph H(G) does not exceed the number of connected components of its low-vertex subgraph L(G). Proof of Theorem 1. Let L(G) and H(G)...

Ngày tải lên: 07/08/2014, 06:22

... graphs described by the lemma had maximum degree 3 and minimum degree 2. There is also a graph with 7 vertices, 10 edges, minimum degree 2, maximum degree 4 with domination number 3. Proposition 4.8. γ r (14, ... δ)-graph with domination number γ. All graphs are either regular or almost regular. The vertices are numbered 0, 1, ,n−1 and the i-th row represen...

Ngày tải lên: 07/08/2014, 06:20

... 2000 Abstract Let γ(n, δ) denote the largest possible domination number for a graph of order n and minimum degree δ. This paper is concerned with the behavior of the right side of the sequence n = γ(n, ... in the case of δ 3 (n). For this it is useful to find circulant graphs of order n with large minimum degree and with domination number at least 3....

Ngày tải lên: 07/08/2014, 06:22

... light of the information available for the total number of matchings of trees, unicyclic graphs, bicyclic graphs, it is natural to consider other classes of g raphs, and the connected graphs with ... π-electron energies with the framewo rk of the HMO approximation [18, 19], the theory of graphic spectra and nullity of graphs; see [3, 9, 10, 11, 1 7]), wher...

Ngày tải lên: 08/08/2014, 12:22

... latex of species of Rhus and is responsible for the oxidation of phenol urushiol, which is contained in the latex, with production of the black resinous lac- quer (Bonner, ... physiological function in the secretory ducts of Rhus. One of the main difficulties encountered in studying its physiological function may be * Prør:::&Jnl !...

Ngày tải lên: 09/08/2014, 03:24

... covering a single number) on each number not covered by an r-mino. The original problem then becomes one of enumerating R (r) n,k , the set of coverings of the row of numbers 1, 2, ,nby kr-minos and ... first and last letters of v c are the same. Consider the r members of C (r)  2m −C (r) ∗ 2m associated with the same word v c starting with r (and thus ending...

Ngày tải lên: 07/08/2014, 13:21

... known, the transfer process in an MT environment places complex requirements on both the linguistic theories involved and on the theories of translation. Perhaps the most refreshing aspect of the ... of semantic organisation that the grammar's seman- tics requires. These categories, and the relationships among them, constitute the upper model. The upper...

Ngày tải lên: 09/03/2014, 01:20

... participated in the making new construction of the q-Bernoulli numbers. EJM carried out the calculation of [1]. JHJ participated in the sequence alignment. SJL performed the correction problem. All ... gave a new construction of these polynomials related to the second kind Stirling numbers and the q-Bernstein polynomials in [1]. The purpose of this paper is to rede...

Ngày tải lên: 20/06/2014, 22:20

... participated in the making new construction of the q-Bernoulli numbers. EJM carried out the calculation of [1]. JHJ participated in the sequence alignment. SJL performed the correction problem. All ... gave a new construction of these polynomials related to the second kind Stirling numbers and the q-Bernstein polynomials in [1]. The purpose of this paper is to rede...

Ngày tải lên: 21/06/2014, 00:20