English
Related papers

Related papers: On Delannoy paths without peaks and valleys

200 papers

Following the work of Cano and Diaz, we consider a continuous analog of lattice path enumeration. This allows us to define a continuous version of any discrete object that counts certain types of lattice paths. We define continuous versions…

Combinatorics · Mathematics 2017-08-09 T. Wakhare , C. Vignat , Q. -N. Le , S. Robins

Using the bijection between partitions and vacillating tableaux, we establish a correspondence between pairs of noncrossing free Dyck paths of length $2n$ and noncrossing partitions of $[2n+1]$ with $n+1$ blocks. In terms of the number of…

Combinatorics · Mathematics 2008-07-27 William Y. C. Chen , Sabrina X. M. Pang , Ellen X. Y. Qu , Richard P. Stanley

A Hamiltonian path (a Hamiltonian cycle) in a graph is a path (a cycle, respectively) that traverses all of its vertices. The problems of deciding their existence in an input graph are well-known to be NP-complete, in fact, they belong to…

Discrete Mathematics · Computer Science 2025-04-02 Nikola Jedličková , Jan Kratochvíl

Let $G$ be a connected graph. The eccentricity of a path $P$, denoted by ecc$_G(P)$, is the maximum distance from $P$ to any vertex in $G$. In the \textsc{Central path} (CP) problem our aim is to find a path of minimum eccentricity. This…

Combinatorics · Mathematics 2022-02-08 Renzo Gómez , Juan Gutiérrez

For $0\leq k \leq n$, the number $C(n,k)$ represents the number of all lattice paths in the plane from the point $(0,0)$ to the point $(n,k)$, using steps $(1,0)$ and $(0,1)$, that never rise above the main diagonal $y=x$. The Fuss-Catalan…

Combinatorics · Mathematics 2025-03-10 Jovan Mikić

We study a new class of palindromic descent polynomials. Given a Dyck path $d$ of semilength $n$ and a permutation $\sigma$ of size $n$, one can label the up-steps and down-steps of $d$ with the elements of $\sigma$. The labeled Dyck path…

Combinatorics · Mathematics 2026-03-25 Danai Deligeorgaki , Krishna Menon

We study upward planar straight-line embeddings (UPSE) of directed trees on given point sets. The given point set $S$ has size at least the number of vertices in the tree. For the special case where the tree is a path $P$ we show that: (a)…

Computational Geometry · Computer Science 2020-12-22 Elena Arseneva , Pilar Cano , Linda Kleist , Tamara Mchedlidze , Saeed Mehrabi , Irene Parada , Pavel Valtr

A lattice path inside the $m\times n$ table $T$ is a sequence $\nu_1,\ldots,\nu_k$ of cells such that $\nu_{j+1}-\nu_j\in\{(1,-1),(1,0),(1,1)\}$ for all $j=1,\ldots,k-1$. The number of lattice paths in $T$ from the first column to the…

Combinatorics · Mathematics 2019-10-23 Mohammad Farrokhi Derakhshandeh Ghouchan

We present a computer-aided, yet fully rigorous, proof of Ira Gessel's tantalizingly simply-stated conjecture that the number of ways of walking $2n$ steps in the region $x+y \geq 0, y \geq 0$ of the square-lattice with unit steps in the…

Combinatorics · Mathematics 2015-05-13 Manuel Kauers , Christoph Koutschan , Doron Zeilberger

The number of Dyck paths of semilength $n$ is famously $C_n$, the $n$th Catalan number. This fact follows after noticing that every Dyck path can be uniquely parsed according to a context-free grammar. In a recent paper, Zeilberger showed…

Combinatorics · Mathematics 2020-09-22 AJ Bu , Robert Dougherty-Bliss

Let $D$ be a digraph. We define the minimum semi-degree of $D$ as $\delta^{0}(D) := \min \{\delta^{+}(D), \delta^{-}(D)\}$. Let $k$ be a positive integer, and let $S = \{s\}$ and $T = \{t_{1}, \dots ,t_{k}\}$ be any two disjoint subsets of…

Combinatorics · Mathematics 2022-08-22 Ansong Ma , Yuefang Sun , Xiaoyan Zhang

Lane-level traversal of (almost) arbitrary input paths is a common problem in the mapping industry. This paper considers the problem of generating \emph{feasible} and maximally convenient lane-level path traversals. The presented approach…

Data Structures and Algorithms · Computer Science 2020-03-06 Dennis Luxen

We prove that every tree of maximum degree $\Delta$ with $\ell$ leaves contains paths between leaves of at least $\log_{\Delta-1}((\Delta-2)\ell)$ distinct lengths. This settles in a strong form a conjecture of Narins, Pokrovskiy and…

Combinatorics · Mathematics 2025-04-18 Francesco Di Braccio , Kyriakos Katsamaktsis , Alexandru Malekshahian

Explainability is becoming an increasingly important topic for deep neural networks. Though the operation in convolutional layers is easier to understand, processing becomes opaque in fully-connected layers. The basic idea in our work is…

Machine Learning · Computer Science 2022-10-04 Ozan İrsoy , Ethem Alpaydın

For a complex polynomial $P$ of degree $n$ and an $m$-tuple of distinct complex numbers $\Lambda=(\lambda_1,\ldots,\lambda_m)$, the dope matrix $D_P(\Lambda)$ is defined as the $m \times (n+1)$ matrix $(c)_{ij}$ with $c_{ij} =1$ if…

Combinatorics · Mathematics 2024-02-21 Ankit Bisain

A separating path system for a graph $G$ is a collection $\mathcal{P}$ of paths in $G$ such that for every two edges $e$ and $f$ in $G$, there is a path in $\mathcal{P}$ that contains $e$ but not $f$. We show that every $n$-vertex graph has…

Combinatorics · Mathematics 2024-05-30 Shoham Letzter

The degree of symmetry of a combinatorial object, such as a lattice path, is a measure of how symmetric the object is. It typically ranges from zero, if the object is completely asymmetric, to its size, if it is completely symmetric. We…

Combinatorics · Mathematics 2021-07-15 Sergi Elizalde

Let $\mathcal{M}=\{m_\lambda\}_{\lambda\in\Lambda}$ be a separating family of lattice seminorms on a vector lattice $X$, then $(X,\mathcal{M})$ is called a multi-normed vector lattice (or MNVL). We write $x_\alpha \xrightarrow{\mathrm{m}}…

Functional Analysis · Mathematics 2017-06-21 Y. A. Dabboorasad , E. Y. Emelyanov , M. A. A. Marabeh

We consider a regular $n$-ary tree of height $h$, for which every vertex except the root is labelled with an independent and identically distributed continuous random variable. Taking motivation from a question in evolutionary biology, we…

Probability · Mathematics 2013-11-14 Matthew I. Roberts , Lee Zhuo Zhao

A digraph $D$ is called \emph{path extendable} if for every nonhamiltonian (directed) path $P$ in $D$, there exists another path $P^\prime$ with the same initial and terminal vertices as $P$, and $V(P^\prime) = V (P)\cup \{w\}$ for a vertex…

Combinatorics · Mathematics 2025-05-01 Zan-Bo Zhang , Weihua He , Hajo Broersma , Xiaoyan Zhang