Results 71 to 80 of about 159,494 (239)
On an Erdős similarity problem in the large
Abstract In a recent paper, Kolountzakis and Papageorgiou ask if for every ε∈(0,1]$\epsilon \in (0,1]$, there exists a set S⊆R$S \subseteq \mathbb {R}$ such that |S∩I|⩾1−ε$\vert S \cap I\vert \geqslant 1 - \epsilon$ for every interval I⊂R$I \subset \mathbb {R}$ with unit length, but that does not contain any affine copy of a given increasing sequence ...
Xiang Gao+2 more
wiley +1 more source
Transitive factorizations of permutations and geometry [PDF]
We give an account of our work on transitive factorizations of permutations. The work has had impact upon other areas of mathematics such as the enumeration of graph embeddings, random matrices, branched covers, and the moduli spaces of curves.
Goulden, I. P., Jackson, D. M.
core
Enumeration of simple random walks and tridiagonal matrices
We present some old and new results in the enumeration of random walks in one dimension, mostly developed in works of enumerative combinatorics. The relation between the trace of the $n$-th power of a tridiagonal matrix and the enumeration of weighted ...
Bauer M+23 more
core +1 more source
C-Finite Sequences and Riordan Arrays
Many prominent combinatorial sequences, such as the Fibonacci, Lucas, Pell, Jacobsthal and Tribonacci sequences, are defined by homogeneous linear recurrence relations with constant coefficients.
Donatella Merlini
doaj +1 more source
ABSTRACT The motivation of this paper is to explore and generalize Sakaguchi‐type functions, which play a significant role in geometric function theory. In this context, we introduce four new classes of analytic univalent functions: ℑΨ,tb,α,ρ,ℑϑb,α,ρ,ℑΘ,mb,α,ρ$$ {\Im}_{\Psi, t}^{b,\alpha, \rho },\kern0.3em {\Im}_{\vartheta}^{b,\alpha, \rho },\kern0.3em
Arzu Akgül
wiley +1 more source
On the Structure of Bispecial Sturmian Words
A balanced word is one in which any two factors of the same length contain the same number of each letter of the alphabet up to one. Finite binary balanced words are called Sturmian words.
Fici, Gabriele
core +1 more source
On the Pre‐ and Post‐Positional Semi‐Random Graph Processes
ABSTRACT We study the semi‐random graph process, and a variant process recently suggested by Nick Wormald. We show that these two processes are asymptotically equally fast in constructing a semi‐random graph G $G$ that has property P ${\mathscr{P}}$, for the following examples of P ${\mathscr{P}}$: (1) P ${\mathscr{P}}$ is the set of graphs containing ...
Pu Gao, Hidde Koerts
wiley +1 more source
Local spectral estimates and quantitative weak mixing for substitution Z${\mathbb {Z}}$‐actions
Abstract The paper investigates Hölder and log‐Hölder regularity of spectral measures for weakly mixing substitutions and the related question of quantitative weak mixing. It is assumed that the substitution is primitive, aperiodic, and its substitution matrix is irreducible over the rationals.
Alexander I. Bufetov+2 more
wiley +1 more source
Extensions of Steiner Triple Systems
ABSTRACT In this article, we study extensions of Steiner triple systems by means of the associated Steiner loops. We recognize that the set of Veblen points of a Steiner triple system corresponds to the center of the Steiner loop. We investigate extensions of Steiner loops, focusing in particular on the case of Schreier extensions, which provide a ...
Giovanni Falcone+2 more
wiley +1 more source
History of Catalan numbers [PDF]
We give a brief history of Catalan numbers, from their first discovery in the 18th century to modern times. This note will appear as an appendix in Richard Stanley's forthcoming book on Catalan numbers.Comment: 10 ...
Pak, Igor
core +1 more source