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Related papers: Rainbow Ramsey problems for the Boolean lattice

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Let $P$ be a poset of size $2^k$ that has a greatest and a least element. We prove that, for sufficiently large $n$, the Boolean lattice $2^{[n]}$ can be partitioned into copies of $P$. This resolves a conjecture of Lonc.

Combinatorics · Mathematics 2016-09-09 Vytautas Gruslys , Imre Leader , István Tomon

Consider the set $[m]\times [n] = \{(i,j)\, : 1\le i \le m, 1\le j \le n\}$ and the equation $x_1+x_2 = x_3$, namely $eq$. The \emph{rainbow number of $[m] \times [n]$ for $eq$}, denoted $\text{rb}([m]\times [n],eq)$, is the smallest number…

Combinatorics · Mathematics 2023-01-26 Kean Fallon , Ethan Manhart , Joe Miller , Hunter Rehm , Nathan Warnberg , Laura Zinnel

For graphs $G^<$ and $H^<$ with linearly ordered vertex sets, the \ordered Ramsey number $r_<(G^<,H^<)$ is the smallest positive integer $N$ such that any red-blue coloring of the edges of the complete ordered graph $K^<_N$ on $N$ vertices…

Combinatorics · Mathematics 2023-05-30 Martin Balko , Marian Poljak

The typical problem in (generalized) Ramsey theory is to find the order of the largest monochromatic member of a family F (for example matchings, paths, cycles, connected subgraphs) that must be present in any edge coloring of a complete…

Combinatorics · Mathematics 2013-04-04 András Gyárfás , Gábor N. Sárközy , Stanley Selkow

The generalized Ramsey number $f(n, p, q)$ is the smallest number of colors needed to color the edges of the complete graph $K_n$ so that every $p$-clique spans at least $q$ colors. Erd\H{o}s and Gy\'arf\'as showed that $f(n, p, q)$ grows…

Combinatorics · Mathematics 2024-08-14 Patrick Bennett , Ryan Cushman , Andrzej Dudek

For positive integers $n,r,s$ with $r > s$, the set-coloring Ramsey number $R(n;r,s)$ is the minimum $N$ such that if every edge of the complete graph $K_N$ receives a set of $s$ colors from a palette of $r$ colors, then there is guaranteed…

Combinatorics · Mathematics 2022-06-24 David Conlon , Jacob Fox , Xiaoyu He , Dhruv Mubayi , Andrew Suk , Jacques Verstraete

We study the multicolor Ramsey numbers for paths and even cycles, $R_k(P_n)$ and $R_k(C_n)$, which are the smallest integers $N$ such that every coloring of the complete graph $K_N$ has a monochromatic copy of $P_n$ or $C_n$ respectively.…

Combinatorics · Mathematics 2018-01-15 Charlotte Knierim , Pascal Su

Given a collection of colored chain posets, we estimate the number of colored subsets of the boolean lattice which avoid all chains in the collection.

Combinatorics · Mathematics 2019-05-06 Hunter Spink , Marius Tiba

We call the minimum order of any complete graph so that for any coloring of the edges by $k$ colors it is impossible to avoid a monochromatic or rainbow triangle, a Mixed Ramsey number. For any graph $H$ with edges colored from the above…

Combinatorics · Mathematics 2014-03-18 Marcus Bartlett , Elliot Krop , Thuhong Nguyen , Michael Ngo , Petra President

The Ramsey number r_k(s,n) is the minimum N such that every red-blue coloring of the k-tuples of an N-element set contains either a red set of size s or a blue set of size n, where a set is called red (blue) if all k-tuples from this set…

Combinatorics · Mathematics 2008-08-28 David Conlon , Jacob Fox , Benny Sudakov

The bipartite Ramsey number $B(n_1,n_2,\ldots,n_t)$ is the least positive integer $b$ such that, any coloring of the edges of $K_{b,b}$ with $t$ colors will result in a monochromatic copy of $K_{n_i,n_i}$ in the $i-$th color, for some $i$,…

Combinatorics · Mathematics 2021-08-10 Yaser Rowshan , Mostafa Gholami

Let $R_k(H;K_m)$ be the smallest number $N$ such that every coloring of the edges of $K_{N}$ with $k+1$ colors has either a monochromatic $H$ in color $i$ for some $1\leqslant i\leqslant k$, or a monochromatic $K_{m}$ in color $k+1$. In…

Combinatorics · Mathematics 2021-10-20 Zixiang Xu , Gennian Ge

A model named `Colored Percolation' has been introduced with its infinite number of versions in two dimensions. The sites of a regular lattice are randomly occupied with probability $p$ and are then colored by one of the $n$ distinct colors…

Statistical Mechanics · Physics 2017-09-13 Sumanta Kundu , S. S. Manna

The Rainbow k-Coloring problem asks whether the edges of a given graph can be colored in $k$ colors so that every pair of vertices is connected by a rainbow path, i.e., a path with all edges of different colors. Our main result states that…

Data Structures and Algorithms · Computer Science 2016-02-19 Łukasz Kowalik , Juho Lauri , Arkadiusz Socała

The Ramsey number $r(t;\ell)$ is the smallest $n$ such that every $\ell$-coloring of the edges of $K_n$ gives a monochromatic $K_{t}$. In recent years, there have been several improvements on asymptotic lower bounds for these numbers when…

Combinatorics · Mathematics 2026-02-03 Yamaan Attwa , Albert López Vidal , Patrick Morris

For a ring R and system L of linear homogeneous equations, we call a coloring of the nonzero elements of R minimal for L if there are no monochromatic solutions to L and the coloring uses as few colors as possible. For a rational number q…

Combinatorics · Mathematics 2010-09-23 Boris Alexeev , Jacob Fox , Ron Graham

A well-known result by Graham in Euclidean Ramsey Theory states that, for every positive real number $A$, every coloring of the plane with finite number of colors contains a monochromatic triangle of area $A$. We consider canonical versions…

Combinatorics · Mathematics 2026-03-17 Sukumar Das Adhikari , Tássio Naia , Oriol Serra

Let $P_t$ denote the path on $t$ vertices. The $r$-coloured Ramsey number of $P_t$, denoted by $R_r(P_t)$, is the minimum integer $n$ such that whenever the complete graph on $n$ vertices is given an $r$-edge-colouring, there exists a…

Combinatorics · Mathematics 2021-08-17 Henry Liu , Bojan Mohar , Yongtang Shi

For graphs $G_1,\ldots,G_k$, the Ramsey number $R(G_1,\ldots,G_k)$ is the smallest positive integer $N$ such that every $k$-edge-coloring of $K_N$ contains a monochromatic copy of $G_i$ in color $i$ for some $i\in[k]$. The Gallai--Ramsey…

Combinatorics · Mathematics 2026-05-05 Yanbo Zhang , Qian Chen , Yaojun Chen

For a graph $G$, a hypergraph $\mathcal{H}$ is a Berge copy of $G$ (or a Berge-$G$ in short), if there is a bijection $f : E(G) \rightarrow E(\mathcal{H})$ such that for each $e \in E(G)$ we have $e \subseteq f(e)$. We denote the family of…

Combinatorics · Mathematics 2019-05-08 Dániel Gerbner , Abhishek Methuku , Gholamreza Omidi , Máté Vizer