Báo cáo toán học: "Balanced online Ramsey games in random graphs" docx
Báo cáo toán học: "Pseudo-regular spectral functions in Krein spaces " docx
... class="bi x0 y0 w1 h 1" alt =""
Báo cáo toán học: " Balanced Gray Codes" pot
... [2], we will call a Gray code balanced if for any two bit
positions i and j, |TC(i) − TC(j)|≤2. Thus, the BRCG is totally balanced for n =1, 2,
balanced for n =1, 2, 3, but unbalanced for n ≥ 4.
It ... an
n
-bit binary Gray code can be viewed as
a Hamilton path in the
n
-cube and a cyclic binary Gray code as a Hamilton cycle. One such
cyclic Gray code, the Binary Reflected Gray...
Báo cáo toán học: "Some New Ramsey Colorings" ppt
... Kalbfleisch. Chromatic Graphs and Ramsey s Theorem. Ph.D. Thesis. University of
Waterloo, January, 1966.
[3] K. Piwakowski. Applying Tabu Search to Determine New Ramsey Graphs. Electronic
J. Combinatorics. ... 19, 1998; Accepted: May 14, 1998.
Abstract
New lower bounds for 15 classical Ramsey numbers are established. Several of the
colorings are found using a new variation of local...
Báo cáo toán học: "Asymptotically optimal tree-packings in regular graphs" pps
... t.
Proof. Partition the set of vertices V into t subsets V
1
,V
2
, ,V
t
by choosing for each
vertex randomly and independently an index i in {1, ,t} and placing it into V
i
.For
v ∈ V (G)and1≤ i ≤ t,letA
i,v
denote ... certain regularity and local density conditions on H,
one can find an almost perfect matching M in H, i.e., the number of vertices in no edge
of M is negligible. In fac...
Báo cáo toán học: "Generalizing the Ramsey Problem through Diameter" doc
... this minimum. Since one
of these functions is increasing in ∆ and the other is decreasing in ∆, the choice of ∆ that
minimizes the maximum (for fixed a) is that for which the two quantities are equal. ... clique, the problem is hopeless
if d =1. Thecased = 2 was settled in [10], where nontrivial constructions were obtained
that matched the trivial lower bounds asymptotically. We...
Báo cáo khoa học:Finding Induced Acyclic Subgraphs in Random Digraphs docx
... Finding Induced Acyclic Subgraphs in Random
Digraphs
C.R. Subramanian
The Institute of Mathematical Sciences
Taramani, Chennai - 600 113, India.
crs@imsc.res .in
Submitted: Oct ... sparse random digraphs (obtained by choosing the arcs
with probability n
−1+o(1)
), the ratio is in fact O(1). Thus, for random digraphs, one can
obtain a significant improvement in the quali...
Báo cáo toán học: "On some Ramsey and Tur´n-type numbers for paths a and cycles" doc
... 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...
Báo cáo toán học: "An Anti-Ramsey Condition on Tree" potx
... ∞. The
second natural question is whether or not we can determine AR(H; b). The first question
is answered in [1] by construction, which yields a partial answer to the second.
Definition 1. For ... same color, exactly one
such edge can be used, implying C
v
(R) contains a vertex corresponding to one in L(H
),
a contradiction.!
Now, let T
0
= T , i = 0, and if T
i
contains a leaf v
i
with ......
Báo cáo toán học: "Balanced online Ramsey games in random graphs" docx
... publication in Combinatorica.
[12] M. Marciniszyn, R. Spăohel, and A. Steger. Online Ramsey games in random graphs.
Accepted for publication in Combinatorics, Probability and Computing.
the electronic ... bounds for online Ramsey games
in random graphs. Accepted for publication in Combinatorics, Probability and Com-
puting.
[14] T. Măutze, R. Spăohel, and H. Thomas....
Báo cáo toán học: "Discrete Morse inequalities on infinite graphs" docx
... Finally, in Section 4 we give an application of
the discrete Morse inequalities which consists on characterizing infinite connected graphs
which admit a discrete Morse function with a fixed number ... criticality of the considered function at the infinite.
In Section 1, we recall basic Forman’s definitions of discrete Morse function and critical
simplex as well as his discrete Mors...
Báo cáo toán hoc:"Vertex-oriented Hamilton cycles in directed graphs" pot
... D. A directed
Hamilton cycle H in D is a Hamilton cycle in the graph underlying D such that all pairs of
consecutive arcs in H form a directed path in D. An anti -directed Hamilton cycle H in D
is ... ideas of a directed Hamilton cycle and an an anti -directed Hamilton cycle, because
a directed Hamilton cycle in D is a (∅, V (D)) vertex-oriented Hamilton cy...
Báo cáo toán học: "Entrywise Bounds for Eigenvectors of Random Graphs" docx
... entrywise bounds for second and lower eigenvectors of
adjacency matrix of Planted partition models. We make a step towards resolving these
questions through computing entrywise bounds for the second ... entrywise
perturbation for eigenvectors of Random graphs, i.e. v
1
(A) −v
1
(E(A))
∞
(where v
1
(M)
is the first eigenvector of a square symmetric matrix M). Perturbat...
Báo cáo toán học: "Large bounded degree trees in expanding graphs" pptx
... Finally, in
Section 5, based on this study, we give very short proofs of our main results – Theorems 4,
5, 6 and 7.
2 Embedding trees in expanding graphs
We start by defining a class of expanding ... almost spanning trees in
random graphs, submitted.
[4] J. Friedman and N. Pipp enger, Expanding graphs contain all small trees, Combinator-
ica 7 (1 987), 71–76.
[5] P. Haxell, Tr...
Báo cáo toán học: "On multicolor Ramsey number of paths versus cycles" pdf
... a corollary of more general
results about the asymptotic results of the Ra msey number for three long even cycles.
Recently, determination of some exact values of Ramsey numbers of type R( P
i
, ... three-color Ramsey numbers for paths versus a cycle, see [3, 4, 5, 13].
In this paper, we provide the exact value of the Ramsey numbers R(P
n
1
, P
n
2
, . . . , P
n
t
, C...
Báo cáo toán học: "The Bipartite Ramsey Numbers b(C2m; K2,2)" pot
... Henning, Bipartite Ramsey numbers, Utilitas Math. 53 (1998)
217–230.
[5] J. H. Hattingh, M. A. Henning, Star-path bipartite Ramsey numbers, Discrete Math.
185 (1998) 255–258.
[6] R. W. Irving, A bipartite ... K
1,n
and K
2,n
− K
2,n
bipartite Ramsey
numbers, Discrete Math. 223 (2000) 83–92.
[3] R. J. Faudree, R. H. Schelp, Path-path Ramsey- type numb ers f or the complete
b...
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