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We consider a distributed computing system in which a master node coordinates $N$ workers to evaluate a function over $n$ input files, where this function accepts general decomposition. In particular, we focus on the general case where the…

Information Theory · Computer Science 2026-04-21 Javad Maheri , K. K. Krishnan Namboodiri , Petros Elia

We present the first combinatorial scheme for counting labelled 4-regular planar graphs through a complete recursive decomposition. More precisely, we show that the exponential generating function of labelled 4-regular planar graphs can be…

Combinatorics · Mathematics 2019-07-26 Marc Noy , Clément Requilé , Juanjo Rué

A triangle decomposition of a graph $G$ is a partition of the edges of $G$ into triangles. Two necessary conditions for $G$ to admit such a decomposition are that $|E(G)|$ is a multiple of three and that the degree of any vertex in $G$ is…

Combinatorics · Mathematics 2016-12-14 Kim Nguyen Pham , Landon Settle , Kayla Wright , Padraic Bartlett

The random greedy algorithm for constructing a large partial Steiner-Triple-System is defined as follows. Begin with a complete graph on $n$ vertices and proceed to remove the edges of triangles one at a time, where each triangle removed is…

Combinatorics · Mathematics 2012-10-29 Tom Bohman , Alan Frieze , Eyal Lubetzky

In this note, we introduce a new method for constructing graphs with high chromatic number and small clique. Indeed, via this method, we present a new proof for the well-known Kneser's conjecture.

Combinatorics · Mathematics 2017-09-12 Hamid Reza Daneshpajouh

A construction described by the current author in 2017 uses two linear `prototype' graphs to build a compound graph with Ramsey properties inherited from the prototypes. This paper describes a generalisation of that construction which has…

Combinatorics · Mathematics 2021-09-13 Fred Rowley

Regular chains and triangular decompositions are fundamental and well-developed tools for describing the complex solutions of polynomial systems. This paper proposes adaptations of these tools focusing on solutions of the real analogue:…

Symbolic Computation · Computer Science 2010-05-17 Changbo Chen , James H. Davenport , John P. May , Marc Moreno Maza , Bican Xia , Rong Xiao

In this article we give a classification of the sub-groups in PSL(2,Z) and of the conjugacy classes of these sub-groups by the mean of an combinatorial invariant: some trivalent diagrams (dotted or not). We give explicit formulae enabling…

Combinatorics · Mathematics 2007-05-23 Samuel Alexandre Vidal

A constructive method is provided that outputs a directed graph which is named a broken crown graph, containing $5n-9$ vertices and $k$ Hamiltonian cycles for any choice of integers $n \geq k \geq 4$. The construction is not designed to be…

Combinatorics · Mathematics 2019-02-28 Michael Haythorpe

We define a triangle design as a partition of the set of lines of a projective space into triangles, where a triangle consists of three pairwise intersecting lines with no common point. A triangle design is balanced if all points are…

Combinatorics · Mathematics 2025-07-10 Minjia Shi , Xiaoxiao Li , Denis S. Krotov

This paper introduces a new systematic algorithm for constructing periodic Euclidean weaving diagrams with combinatorial arguments. It is shown that such a weaving diagram can be considered as a specific type of four-regular periodic planar…

Combinatorics · Mathematics 2022-06-24 Mizuki Fukuda , Motoko Kotani , Sonia Mahmoudi

In this article we construct uncountably many new homogeneous locally finite Steiner triple systems of countably infinite order as Fra\"{\i}ss\'{e} limits of classes of finite Steiner triple systems avoiding certain subsystems. The…

Combinatorics · Mathematics 2021-03-10 Daniel Horsley , Bridget S. Webb

The 2-block intersection graph (2-BIG) of a twofold triple system (TTS) is the graph whose vertex set is composed of the blocks of the TTS and two vertices are joined by an edge if the corresponding blocks intersect in exactly two elements.…

Combinatorics · Mathematics 2020-12-29 Rosalind A. Cameron , David A. Pike

In 1970 Lov\'asz conjectured that every connected vertex-transitive graph admits a Hamilton cycle, apart from five exceptional graphs. This conjecture has recently been settled for graphs defined by intersecting set systems, which feature…

Combinatorics · Mathematics 2023-11-16 Torsten Mütze

In 2004, Karo\'nski, \L uczak and Thomason proposed $1$-$2$-$3$-conjecture: For every nice graph $G$ there is an edge weighting function $ w:E(G)\rightarrow\{1,2,3\} $ such that the induced vertex coloring is proper. After that, the total…

Combinatorics · Mathematics 2022-05-02 Akbar Davoodi , Leila Maherani

As a consequence of the classification of the finite simple groups, it has been possible in recent years to characterize Steiner t-designs, that is t-(v,k,1) designs, mainly for t = 2, admitting groups of automorphisms with sufficiently…

Combinatorics · Mathematics 2018-07-03 Michael Huber

We offer a new structural basis for the theory of 3-connected graphs, providing a unique decomposition of every such graph into parts that are either quasi 4-connected, wheels, or thickened $K_{3,m}$'s. Our construction is explicit,…

Combinatorics · Mathematics 2025-07-25 Johannes Carmesin , Jan Kurkofka

Graph polytopes arising from vertex-weighted graphs were first introduced by B\'ona, Ju, and Yoshida. We prove a conjecture stating that for any simple connected graph, the numerator polynomial of the Ehrhart series of its graph polytope is…

Combinatorics · Mathematics 2026-04-13 Feihu Liu

In this article, three types of joins are introduced for subspaces of a vector space. Decompositions of the Gra{\ss}mannian into joins are discussed. This framework admits a generalization of large set recursion methods for block designs to…

Combinatorics · Mathematics 2025-10-02 Michael Braun , Michael Kiermaier , Axel Kohnert , Reinhard Laue

In 2014, Keevash famously proved the existence of $(n,q,r)$-Steiner systems as part of settling the Existence Conjecture of Combinatorial Designs (dating from the mid-1800s). In 2020, Glock, K\"uhn, and Osthus conjectured a minimum degree…

Combinatorics · Mathematics 2025-10-09 Michelle Delcourt , Thomas Lesgourgues , Luke Postle