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Related papers: Circles and Paths in 2-Colored Best Match Graphs

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We study a version of online edge coloring, where the goal is to color as many edges as possible using only a given number, $k$, of available colors. All of our results are with regard to competitive analysis. Previous attempts to identify…

Data Structures and Algorithms · Computer Science 2016-10-26 Lene M. Favrholdt , Jesper W. Mikkelsen

In the Properly Colored Spanning Tree problem, we are given an edge-colored undirected graph and the goal is to find a properly colored spanning tree, i.e., a spanning tree in which any two adjacent edges have distinct colors. The problem…

Data Structures and Algorithms · Computer Science 2024-02-02 Yuhang Bai , Kristóf Bérczi , Gergely Csáji , Tamás Schwarcz

Using the definition of colouring of $2$-edge-coloured graphs derived from $2$-edge-coloured graph homomorphism, we extend the definition of chromatic polynomial to $2$-edge-coloured graphs. We find closed forms for the first three…

Combinatorics · Mathematics 2020-07-28 I. Beaton , D. Cox , C. Duffy , N. Zolkavich

In phylogenetics, evolution is traditionally represented in a tree-like manner. However, phylogenetic networks can be more appropriate for representing evolutionary events such as hybridization, horizontal gene transfer, and others. In…

Data Structures and Algorithms · Computer Science 2024-10-18 Manuel Lafond , Vincent Moulton

The evolutionary relationships among organisms have traditionally been represented using rooted phylogenetic trees. However, due to reticulate processes such as hybridization or lateral gene transfer, evolution cannot always be adequately…

Populations and Evolution · Quantitative Biology 2022-01-20 Sungsik Kong , Joan Carles Pons , Laura Kubatko , Kristina Wicke

We investigate the relationship between two kinds of vertex colorings of hypergraphs: unique-maximum colorings and conflict-free colorings. In a unique-maximum coloring, the colors are ordered, and in every hyperedge of the hypergraph the…

Combinatorics · Mathematics 2012-06-12 Panagiotis Cheilaris , Balázs Keszegh , Dömötör Pálvölgyi

We introduce two novel evolutionary formulations of the problem of coloring the nodes of a graph. The first formulation is based on the relationship that exists between a graph's chromatic number and its acyclic orientations. It views such…

Neural and Evolutionary Computing · Computer Science 2007-05-23 V. C. Barbosa , C. A. G. Assis , J. O. do Nascimento

Tree representations of (sets of) symmetric binary relations, or equivalently edge-colored undirected graphs, are of central interest, e.g.\ in phylogenomics. In this context symbolic ultrametrics play a crucial role. Symbolic ultrametrics…

Discrete Mathematics · Computer Science 2015-09-18 Marc Hellmuth , Nicolas Wieseke

In the present paper, we study algorithmic questions for the arc-intersection graph of directed paths on a tree. Such graphs are known to be perfect (proved by Monma and Wei in 1986). We present faster algorithms than all previously known…

Discrete Mathematics · Computer Science 2009-02-10 Olivier Durand de Gévigney , Frédéric Meunier , Christian Popa , Julien Reygner , Ayrin Romero

In this paper we consider Contact graphs of Paths on a Grid (CPG graphs), i.e. graphs for which there exists a family of interiorly disjoint paths on a grid in one-to-one correspondence with their vertex set such that two vertices are…

Computational Geometry · Computer Science 2018-09-07 Zakir Deniz , Esther Galby , Andrea Munaro , Bernard Ries

Tree-based phylogenetic networks, which may be roughly defined as leaf-labeled networks built by adding arcs only between the original tree edges, have elegant properties for modeling evolutionary histories. We answer an open question of…

Best match graphs (BMGs) are vertex-colored directed graphs that were introduced to model the relationships of genes (vertices) from different species (colors) given an underlying evolutionary tree that is assumed to be unknown. In…

Computational Complexity · Computer Science 2020-12-04 David Schaller , Peter F. Stadler , Marc Hellmuth

Rooted acyclic graphs appear naturally when the phylogenetic relationship of a set $X$ of taxa involves not only speciations but also recombination, horizontal transfer, or hybridization, that cannot be captured by trees. A variety of…

Populations and Evolution · Quantitative Biology 2022-04-29 Marc Hellmuth , David Schaller , Peter F. Stadler

Maximal planar graph refers to the planar graph with the most edges, which means no more edges can be added so that the resulting graph is still planar. The Four-Color Conjecture says that every planar graph without loops is 4-colorable.…

General Mathematics · Mathematics 2012-10-26 Jin Xu

2-quasi best match graphs (2-qBMGs) are directed graphs that capture a notion of close relatedness in phylogenetics. Here, we investigate the undirected underlying graph of a 2-qBMG (un-2qBMG) and show that they contain neither a path $P_l$…

Combinatorics · Mathematics 2025-12-08 Annachiara Korchmaros , Peter F. Stadler

Phylogenetic networks are a type of directed acyclic graph that represent how a set $X$ of present-day species are descended from a common ancestor by processes of speciation and reticulate evolution. In the absence of reticulate evolution,…

Combinatorics · Mathematics 2017-08-11 Andrew Francis , Charles Semple , Mike Steel

We characterize the compatibility of a collection of unrooted phylogenetic trees as a question of determining whether a graph derived from these trees --- the display graph --- has a specific kind of triangulation, which we call legal. Our…

Discrete Mathematics · Computer Science 2010-04-26 Sudheer Vakati , David Fernández-Baca

Point-determining graphs are graphs in which no two vertices have the same neighborhoods, co-point-determining graphs are those whose complements are point-determining, and bi-point-determining graphs are those both point-determining and…

Combinatorics · Mathematics 2009-11-10 Ira Gessel , Ji Li

Deciding whether a collection of unrooted trees is compatible is a fundamental problem in phylogenetics. Two different graph-theoretic characterizations of tree compatibility have recently been proposed. In one of these, tree compatibility…

Discrete Mathematics · Computer Science 2012-10-16 Sudheer Vakati , David Fernández-Baca

In the Coloured Clustering problem, we wish to colour vertices of an edge coloured graph to produce as many stable edges as possible, i.e., edges with the same colour as their ends. In this paper, we reveal that the problem is in fact a…

Data Structures and Algorithms · Computer Science 2018-07-30 Leizhen CAI , On Yin LEUNG