Results 141 to 150 of about 235,748 (327)

Classical Hurwitz numbers and related combinatorics

, 2016
In 1891 Hurwitz [30] studied the number Hg,d of genus g ≥ 0 and degree d ≥ 1 coverings of the Riemann sphere with 2g + 2d− 2 fixed branch points and in particular found a closed formula for Hg,d for any fixed d.
B. Dubrovin, Di Yang, D. Zagier
semanticscholar   +1 more source

Short survey about combinatorics on words and algorithmic methods in a ring (draft) [PDF]

arXiv, 2016
A short survey about combinatorics on words and algorithmic methods in a ring. Special attention is given to Shirshov's results. Adopted for undegraduate students.
arxiv  

Combinatorics of Type D Exceptional Sequences [PDF]

arXiv, 2020
Exceptional sequences are important sequences of quiver representations in the study of representation theory of algebras. They are also closely related to the theory of cluster algebras and the combinatorics of Coxeter groups. We combinatorially classify exceptional sequences of a family of type D Dynkin quivers, and we show how our model for ...
arxiv  

Combinatorics of Chord Progressions [PDF]

, 2012
Color poster with text and diagrams.This study explored an overlap between combinatorics and music. The goal was to show chord progressions that are common to a specific collection of music, composer, or era.University of Wisconsin--Eau Claire Office of
Kiefer, Peter
core   +1 more source

Putatively Optimal Projective Spherical Designs With Little Apparent Symmetry

Journal of Combinatorial Designs, Volume 33, Issue 6, Page 222-234, June 2025.
ABSTRACT We give some new explicit examples of putatively optimal projective spherical designs, that is, ones for which there is numerical evidence that they are of minimal size. These form continuous families, and so have little apparent symmetry in general, which requires the introduction of new techniques for their construction.
Alex Elzenaar, Shayne Waldron
wiley   +1 more source

Combinatorics in the Art of the Twentieth Century [PDF]

, 2017
This paper is motivated by a question I asked myself: How can combinatorial structures be used in a work of art? Immediately, other questions arose: Whether there are artists that work or think combinatorially?
Barrière Figueroa, Eulalia
core  

The Moran Process on a Random Graph

Random Structures &Algorithms, Volume 66, Issue 3, May 2025.
ABSTRACT We study the fixation probability for two versions of the Moran process on the random graph Gn,p$$ {G}_{n,p} $$ at the threshold for connectivity. The Moran process models the spread of a mutant population in a network. Throughout the process, there are vertices of two types, mutants, and non‐mutants.
Alan Frieze, Wesley Pegden
wiley   +1 more source

On Rainbow Turán Densities of Trees

Random Structures &Algorithms, Volume 66, Issue 3, May 2025.
ABSTRACT For a given collection 𝒢=(G1,…,Gk) of graphs on a common vertex set V$$ V $$, which we call a graph system, a graph H$$ H $$ on a vertex set V(H)⊆V$$ V(H)\subseteq V $$ is called a rainbow subgraph of 𝒢 if there exists an injective function ψ:E(H)→[k]$$ \psi :E(H)\to \left[k\right] $$ such that e∈Gψ(e)$$ e\in {G}_{\psi (e)} $$ for each e∈E(H)$$
Seonghyuk Im, Jaehoon Kim, Hyunwoo Lee, Haesong Seo   +3 more
wiley   +1 more source

Being Aware of Data Leakage and Cross‐Validation Scaling in Chemometric Model Validation

Journal of Chemometrics, Volume 39, Issue 4, April 2025.
ABSTRACT The main goal of our investigation is to raise awareness among chemometricians about how easy it is to introduce data or parameter leakage by inappropriate methods and to demonstrate that high precision is necessary in the interpretation of opinions found in the literature on the preference of leave‐one‐out, leave‐many‐out, and repeated cross ...
Péter Király, Gergely Tóth
wiley   +1 more source