Results 11 to 20 of about 524 (71)
All finite sets are Ramsey in the maximum norm
For two metric spaces $\mathbb X$ and $\mathcal Y$ the chromatic number $\chi ({{\mathbb X}};{{\mathcal{Y}}})$ of $\mathbb X$ with forbidden $\mathcal Y$ is the smallest k such that there is a colouring of the points of $\mathbb X$ with k colors that ...
Andrey Kupavskii, Arsenii Sagdeev
doaj +1 more source
Star-Critical Ramsey Numbers for Cycles Versus K4
Given three graphs G, H and K we write K → (G, H), if in any red/blue coloring of the edges of K there exists a red copy of G or a blue copy of H. The Ramsey number r(G, H) is defined as the smallest natural number n such that Kn → (G, H) and the star ...
Jayawardene Chula J. +2 more
doaj +1 more source
Gallai-Ramsey Numbers for Rainbow S3+S_3^ + and Monochromatic Paths
Motivated by Ramsey theory and other rainbow-coloring-related problems, we consider edge-colorings of complete graphs without rainbow copy of some fixed subgraphs.
Li Xihe, Wang Ligong
doaj +1 more source
Background – Because of the increased incidence of multidrug‐resistant (MDR) bacteria, the use of disinfectants over antibiotics has been encouraged. However, the interactions between disinfectants and host local immunity are poorly understood. Objective – To assess the effects of chlorhexidine digluconate (Chx), with and without selected host defence ...
Domenico Santoro +3 more
wiley +1 more source
Singular Turán Numbers and Worm-Colorings
A subgraph G of H is singular if the vertices of G either have the same degree in H or have pairwise distinct degrees in H. The largest number of edges of a graph on n vertices that does not contain a singular copy of G is denoted by TS(n, G).
Gerbner Dániel +3 more
doaj +1 more source
A structure theorem for stochastic processes indexed by the discrete hypercube
Let A be a finite set with , let n be a positive integer, and let $A^n$ denote the discrete $n\text {-dimensional}$ hypercube (that is, $A^n$ is the Cartesian product of n many copies of A).
Pandelis Dodos, Konstantinos Tyros
doaj +1 more source
Tower Gaps in Multicolour Ramsey Numbers
Resolving a problem of Conlon, Fox and Rödl, we construct a family of hypergraphs with arbitrarily large tower height separation between their $2$ -colour and q-colour Ramsey numbers.
Quentin Dubroff +3 more
doaj +1 more source
Ramsey numbers of partial order graphs (comparability graphs) and implications in ring theory
For a partially ordered set (A,≤)(A,\le ), let GA{G}_{A} be the simple, undirected graph with vertex set A such that two vertices a≠b∈Aa\ne b\in A are adjacent if either a≤ba\le b or b≤ab\le a.
Badawi Ayman, Rissner Roswitha
doaj +1 more source
An improved lower bound for Folkman's theorem [PDF]
Folkman's Theorem asserts that for each $k \in \mathbb{N}$, there exists a natural number $n = F(k)$ such that whenever the elements of $[n]$ are two-coloured, there exists a set $A \subset [n]$ of size $k$ with the property that all the sums of the form
Balogh, József +4 more
core +2 more sources
Zarankiewicz’s problem for semilinear hypergraphs
A bipartite graph $H = \left (V_1, V_2; E \right )$ with $\lvert V_1\rvert + \lvert V_2\rvert = n$ is semilinear if $V_i \subseteq \mathbb {R}^{d_i}$ for some $d_i$ and the edge relation E consists of the pairs of points $(
Abdul Basit +4 more
doaj +1 more source

