Báo cáo toán học: "Graceful Tree Conjecture for Infinite Trees" pptx

... upper domination numbers, in symbols: Γ(G  H) ≥ Γ(G)Γ(H ). A conjecture posed by Vizing [7] in 1968 claims that Vizing’s conjecture: For any graphs G and H, γ(G  H) ≥ γ(G)γ(H), where γ, as usual, ... proposed the following Conjecture (Nowakowski, Rall): For any graphs G and H, Γ(G  H) ≥ Γ(G)Γ(H), where Γ denotes the upper domination of a graph. In this note we prove this conjectu...

Ngày tải lên: 07/08/2014, 08:22

... necessary condition is not sufficient (Conjecture 5.2, Lee (1990)). 1 the electronic journal of combinatorics 6 (1999), #R23 3 2 The conjecture Conjecture (Conjecture 5.2 of Lee (1990)) A dyadic ... Y − ) ∪ (X − ∩ Y + )| ≤ 4 k for each circuit X and cocircuit Y such that (X + ∩ Y − ) ∪ (X − ∩ Y + ) = ∅. Lee’s conjecture was motivated by (i) the fact that it is true for k = 0, (ii) hi...

Ngày tải lên: 07/08/2014, 06:20

... v, otherwise we write u ∼ v. For subsets of vertices X and Y , we write X ∼ Y if x ∼ y for all x ∈ X, y ∈ Y ; we write X ∼ Y if x ∼ y for all x ∈ X, y ∈ Y . For a vertex x ∈ Y , we write ... for any graph H on k vertices and for any graph G which is not isomorphic to H, G −→ H. We explicitly describe all exceptional cases. This determines the induced vertex- anti-Ramsey numbe...

Ngày tải lên: 07/08/2014, 15:22

... Theory [17]. A straightforward counting argument shows that a trivial lower bound for the size k of a dense set in P G(2, q) is k ≥ √ 2q, see e.g. [19]. On the other hand, for q square there is ... possibilities for subgroups H 1 is then less than or equal to the number of subgroups of H of size p s−1 containing S 1 , which is p s−t −1 p−1 . Also, for a fixed H 1 , there is at most one...

Ngày tải lên: 07/08/2014, 15:23

... transversal of the family of oriented cuts of  G if F ∩ B = ∅ for all oriented cuts B in  G. In 1978, Woodall [7] conjectured that, for any oriented graph  G, a minimum oriented cut in  G has ... of oriented cuts. Woodall’s conjecture has been proved in some particular cases. Feofiloff and Younger [2], and independently Schrijver [6], proved this conjecture for source-sink connec...

Ngày tải lên: 07/08/2014, 07:21

... b)-partition for every pair (a, b) of positive integers such that a + b = τ(G), then we say that G is τ-partitionable. The following conjecture is known as the Path Partition Conjecture (or the PPC, for ... (w j ) for all k such that i ≤ k ≤ j. If i ≤ s and j ≥ s +1, then N I (w k ) ⊆ N I (w i ) ∩ N (w j ) for all k such that k ≤ i or k ≥ j. Let q =  |W | p  and put W i = {w (i−...

Ngày tải lên: 07/08/2014, 13:21

... 05A15,05A19,05C30 Abstract This note deals with a formula due to G. Labelle for the summed cycle indices of all rooted trees, which resembles the well-known formula for the cycle index of the symmetric group ... =n c 1 >0 c c 1 −1 1 s c 1 1 c 1 !  i>1 1 c i !i c i   j|i jc j  c i −1   j|i,j=i jc j  s c i i .  As a second corollary, we obtain Cayley’s formula for the numbe...

Ngày tải lên: 07/08/2014, 13:21

... compari- son to the other treebanks, making the inverse trans- formation for PADT more problematic than for the other treebanks. The absence of a positive effect for PADT is therefore understandable ... transformations boosts the perfor- mance of MaltParser for all treebanks and in two cases out of four outperforms MSTParser (which was the top scoring system for all four treebanks)....

Ngày tải lên: 17/03/2014, 04:20

... t 2 , t 0 [{0, 1}] = {t 1 , t 2 }, and t 1 .p = t 0 . 5 Tree kernels for dependency trees We now define a kernel function for dependency trees. The tree kernel is a function K(T 1 , T 2 ) that returns ... parse tree to a dependency tree. For example, subjects are de- pendent on their verbs and adjectives are dependent Troops Tikrit advanced near t t t t 0 1 2 3 Figure 1: A depende...

Ngày tải lên: 17/03/2014, 06:20

... and distributed freely for any purposes (see copyright notice below). Articles in Nanoscale Research Letters are listed in PubMed and archived at PubMed Central. For information about publishing ... silicon Fabry-Pérot films for loading and release of a steroid. Langmuir 2004, 20:11264-11269. Figure 1. The current densities for PSRFs and the coupled density for C-PSRFs....

Ngày tải lên: 20/06/2014, 20:20