Báo cáo toán học: "Recognizing circulant graphs of prime order in polynomial time" doc

... efficient. Recognizing circulant graphs of prime order in polynomial time ∗ Mikhail E. Muzychuk Netanya Academic College 42365 Netanya, Israel mikhail@netvision.net.il Gottfried Tinhofer Technical University of ... W of indices write A W for the submatrix of A consisting of all rows and columns index with elements of W . It is easy to see by inspection that each of the...

Ngày tải lên: 07/08/2014, 06:22

... of working with the interplay between association schemes and S-rings has been successfully employed in [21] for the case of circulants on a prime number of vertices. In this paper we are going ... simple fact can be used in order to reduce the task of constructing a Cayley numbering of G to the task of finding such a numbering for the factor graph G/τ and extending it to...

Ngày tải lên: 07/08/2014, 06:22

... 70 pairs of disjoint triples, 315 pairs of triples which intersect in one point, and 210 pairs of triples which intersect in two points. Since the subgraph induced by L 2 is regular of degree ... construction of the Hoffman-Singleton graph from the 15 points and 35 lines of PG(3, 2), where edges between points and lines indicate incidence, and edges between lines indicate disjo...

Ngày tải lên: 07/08/2014, 08:22

... one we obtain. The problem of determining the behavior of the best possible value of ρ, as well as that of deciding if the n-term can be replaced by O(1), remain open. A weaker version of Corollary ... of the vertices of G into r parts which maximizes the number of crossing edges between the parts. Then for every x ∈ V i and j = i the number of neighbors of x in V i is...

Ngày tải lên: 07/08/2014, 13:21

... the list of all minimal 2 -in nite diagrams, which are cluster alge- braic analogues of extended Dynkin graphs. 1 Introduction Cluster algebras were introduced in [4] by Fomin and Zelevinsky to ... statements in our proof of Lemma 6.1. For the remaining vertices they follow from a direct check. the electronic journal of combinatorics 14 (2007), #R3 21 Recognizing Cluster Algebra...

Ngày tải lên: 07/08/2014, 15:22

... permutation of rows and columns A is a block diagonal matrix in which each block is a square all-1 matrix. Proof of Theorem 1.1: The square of the number of perfect matchings of G counts ordered pairs of ... counts ordered pairs of such matchings. We claim that this is the number of spanning 2-regular subgraphs H of G consisting of even cycles (including cycles of leng...

Ngày tải lên: 07/08/2014, 15:22

... non-decreasing mapping such that φ(v) > 0, v > 0, and φ(0) = 0 where . is any fixed norm on R d . In recent years, there has been an increasing interest in the study of the asymptotic behavior of ... boundedness of the solutions of linear Volterra difference equations, we refer the readers to [10–12]. We give some applications of our main result for sub-linear, linear, and...

Ngày tải lên: 20/06/2014, 20:20

... intra-cell interference, while the interference from the other sites is defined as inter-cell interference. The ratio of the intra-site interference to inter-site interference is defined as R = I intra I inter (14) From ... is 4 × 2 in downlink. For intra-site CoMP, the joint processing with block diagonalization algorithm is adopted [19] since the downlink CSI can be obtained at the eNB...

Ngày tải lên: 20/06/2014, 21:20

... Discussion In this article, we have introduced a testable criterion for robustness for a given cycle of heteroclinic con- nections within constrained settings—this test involves finding the connection ... nonlinear function that represents both the intrinsic firing and that due to interaction with the other cells in the network. These systems have a very rich set of invariant subspaces...

Ngày tải lên: 20/06/2014, 21:20

... journal of combinatorics (2000),#R46 5 are n ≤ 27, and these proofs involve substantial computation as the value of n increases, and the examination of an exponentially increasing number of cases. Before ... be confirmed by using sufficient accuracy in approximating the appropriate root of P (x 1 ) = 0. As is typical in this type of variable elimination, care must be taken in d...

Ngày tải lên: 07/08/2014, 06:20