Báo cáo toán học: "On derivation ranges and the identity operator" pdf

Ngày tải lên: 05/08/2014, 15:20

... necessary conditions of Hopfian and Co -Hopfian modules. In particular, we show that the weakly Co -Hopfian regular module R R is Hopfian, and the left R-module M is Co -Hopfian if and only if the left R[x]/(x n+1 )- module M[x]/(x n+1 ) ... R[x]/(x n+1 )- module M[x]/(x n+1 ) is Co -Hopfian, where n is a positive integer. 2000 Mathematics Subject Classification: Keywords: Hopfian modul...

Ngày tải lên: 06/08/2014, 05:20

... distance is not equal to afixed δ∈{ 1 , ,n} , then a pair of disconnected sets becomes an equidistant code pair . For disconnected sets A and B we will give a bound for |A|·|B| in terms of the eigenvalues ... ,q } n ,thesetofwordsoflengthnoveranalphabetofsize q,anddefinetwowordstobeinrelationR δ iftheirHammingdistance(the numberofcoordinateplacesinwhichtheydiffer)equalsδ.Thisdefines...

Ngày tải lên: 07/08/2014, 06:20

... =1, |V i | = F i for 1 ≤ i ≤ n, |V 0 n | =1and |V i n | = F i for 1 ≤ i ≤ n − 2. On Minimal Words With Given Subword Complexity Ming-wei Wang ∗ Department of Computer Science University of Waterloo Waterloo, ... 2 1. What is the length of a minimal word of order N? 2. Is there a reasonably efficient algorithm that finds such minimal words? 3. For each order how many minimal w...

Ngày tải lên: 07/08/2014, 06:22

... standard(C) and the set of standard marked Catalan trees by standard(C, ∗). The standard trees in C 4 are , , , , . One of the standard trees in CH 3 is . The standard tree representing the class [T ... those trees which are largest in their equivalence class as standard trees, and use them as equivalence class representatives. We will de- note the set of standard...

Ngày tải lên: 07/08/2014, 06:22

... between the self-describing sequences and the Catalan family tree. Theorem 2. The full names of the members of the Catalan family are precisely the self- describing sequences. In other words, they ... proof of Theorem 3 and the reason is that there is an important difference in the distribution of labels in the Catalan family tree and the tree of the...

Ngày tải lên: 07/08/2014, 07:21

... each, and other random variables. Equiprobable allocations are the most simple and well studied. Consider, for example, an Internet voting on the theme: “Which of the N teams will win the world ... is 1/N . Let the ith cell contain m i particles on completion. Then associate with this cell the probability a i = m i /m and withdraw the particles. 2. The other n particle...

Ngày tải lên: 07/08/2014, 07:21

... combinatorics 10 (2003), #R35 14 Bicoloured Dyck paths and the contact polynomial for n non-intersecting paths in a half-plane lattice. R. Brak† and J. W. Essam‡ ∗ †Department of Mathematics, The ... configurations of a single path starting at vertex v i α and ending at vertex v f β . The theorem may be used to find the Hankel n path contact polynomial...

Ngày tải lên: 07/08/2014, 08:20

... paper answers the holey square conjecture in the affirmative via a theorem about tiling parity with applications beyond the problem of the holey square. We demonstrate some of these other consequences. As ... of the proof follows analogously to the case p =1. 3 The holey square As discussed in the introduction, the resolution of the holey square conjecture...

Ngày tải lên: 07/08/2014, 08:22

... On some Ramsey and Tur´an-type numbers for paths and cycles Tomasz Dzido Institute of Mathematics, University of Gda´nsk Wita Stwosza 57, 80-952 Gda´nsk, Poland tdz@math.univ.gda.pl Marek Kubale Algorithms ... is a path of length 3 joining x and y. Now we will show that any path of length at least 3 but shorter than k − 2 which joins x and y can be extended by two addition...

Ngày tải lên: 07/08/2014, 13:21

... between the LR-tableaux A of shape A and 1s in the top boxes of every column and arbitrary LR-tableaux D of shape D, where D is the skew diagram A with the top boxes of every column removed, simply ... A and B. A skew diagram is connected if it does not decay. A skew character whose skew diagram D decays into disconnected (skew) diagrams A, B is equivalent to the product...

Ngày tải lên: 07/08/2014, 15:22

... is r -identifying in all graphs G  that can be obtained from G by deleting at most t edges, we say that C is robust against t known edge deletions. Codes that are robust against t unknown edge ... to study codes that remain identifying, for instance, when some edges are deleted in the underlying graph. In this paper we consider the following two classe...

Ngày tải lên: 07/08/2014, 15:22

... local lemma as in Erd˝os and Spencer [3] and in Albert, Frieze and Reed [1]. We state the lemma as the electronic journal of combinatorics 15 (2008), #R59 7 On rainbow trees and cycles Alan Frieze ∗ Michael ... 4 (a) Let c 0 = 2 −7 and suppose that n ≥ 2 21 . Then every 2c 0 n-bounded edge colouring of K n contains rainbow cycles of length k, n/2 ≤ k ≤ n. (b) If n ≥ e 1000 a...

Ngày tải lên: 07/08/2014, 15:23

... follows since 4 ≤ e(B k (S)) = the electronic journal of combinatorics 16 (2009), #R28 10 On two problems regarding the Hamiltonian cycle game Dan Hefetz Institute of Theoretical Computer Science ETH ... vertices are the edges of K n , and whose hyperedges are the edge sets of all Hamiltonian cycles of K n . In this paper we study the fair Maker-Breaker Hamiltonian c...

Ngày tải lên: 07/08/2014, 21:21

... consider three classes of random graphs: edge random graphs, vertex random graphs, and vertex-edge random graphs. Edge random graphs are Erd ˝ os-R ´ enyi random graphs, vertex random graphs are generalizations ... Every edge random graph is a vertex-edge random graph. (b) Every vertex random graph is a vertex-edge random graph. However, not all generalized edge...

Ngày tải lên: 08/08/2014, 14:23