Sciweavers

DAM
2011
13 years 6 months ago
On the b-coloring of P4-tidy graphs
A b-coloring of a graph is a coloring such that every color class admits a vertex adjacent to at least one vertex receiving each of the colors not assigned to it. The b-chromatic ...
Clara Inés Betancur Velasquez, Flavia Bonom...
COMGEO
2011
ACM
13 years 6 months ago
A computational approach to Conway's thrackle conjecture
A drawing of a graph in the plane is called a thrackle if every pair of edges meets precisely once, either at a common vertex or at a proper crossing. Let t(n) denote the maximum ...
Radoslav Fulek, János Pach
SIAMDM
2010
128views more  SIAMDM 2010»
13 years 10 months ago
Permutation Capacities of Families of Oriented Infinite Paths
K¨orner and Malvenuto asked whether one can find n n/2 linear orderings (i.e., permutations) of the first n natural numbers such that any pair of them places two consecutive int...
Graham Brightwell, Gérard D. Cohen, Emanuel...
SIAMCOMP
2002
139views more  SIAMCOMP 2002»
13 years 11 months ago
Approximating the Domatic Number
A set of vertices in a graph is a dominating set if every vertex outside the set has a neighbor in the set. The domatic number problem is that of partitioning the vertices of a gra...
Uriel Feige, Magnús M. Halldórsson, ...
ENDM
2002
107views more  ENDM 2002»
13 years 11 months ago
Edge-Colorings of Complete Graphs that Avoid Polychromatic Trees
Given a positive integer n and a family F of graphs, let R(n, F) denote the maximum number of colors in an edge-coloring of Kn such that no subgraph of Kn belonging to F has disti...
Tao Jiang, Douglas B. West
DM
2002
93views more  DM 2002»
13 years 11 months ago
New constructions of non-adaptive and error-tolerance pooling designs
We propose two new classes of non-adaptive pooling designs. The first one is guaranteed to be
Hung Q. Ngo, Ding-Zhu Du
DM
2002
81views more  DM 2002»
13 years 11 months ago
On restricted edge-colorings of bicliques
We investigate the minimum and maximum number of colors in edge-colorings of Kn,n such that every copy of Kp,p receives at least q and at most q colors. Along the way we improve t...
Dhruv Mubayi, Douglas B. West
DM
2002
98views more  DM 2002»
13 years 11 months ago
On dijoins
For every nonnegative integer arc weight function
Gérard Cornuéjols, Bertrand Guenin
DM
2002
134views more  DM 2002»
13 years 11 months ago
Covering a hypergraph of subgraphs
Let G be a tree and let H be a collection of subgraphs of G, each having at most d connected components. Let (H) denote the maximum number of members of H no two of which share a ...
Noga Alon
DCG
2002
76views more  DCG 2002»
13 years 11 months ago
The Unit Distance Problem for Centrally Symmetric Convex Polygons
Let f(n) be the maximum number of unit distances determined by the vertices of a convex n-gon. Erdos and Moser conjectured that this function is linear. Supporting this conjecture...
Bernardo M. Ábrego, Silvia Fernández...