Results 81 to 90 of about 69,347 (192)

Conditioned Galton-Watson trees do not grow [PDF]

Discrete Mathematics & Theoretical Computer Science, 2006
An example is given which shows that, in general, conditioned Galton-Watson trees cannot be obtained by adding vertices one by one, while this can be done in some important but special cases, as shown by Luczak and Winkler.
Svante Janson
doaj   +1 more source

Completing Partial k‐Star Designs

Journal of Combinatorial Designs, Volume 33, Issue 12, Page 446-455, December 2025.
ABSTRACT A k‐star is a complete bipartite graph K 1 , k. A partial k‐star design of order n is a pair ( V , A ) where V is a set of n vertices and A is a set of edge‐disjoint k‐stars whose vertex sets are subsets of V. If each edge of the complete graph with vertex set V is in some star in A, then ( V , A ) is a (complete) k‐star design.
Ajani De Vas Gunasekara, Daniel Horsley
wiley   +1 more source

A fixed point theorem for Boolean networks expressed in terms of forbidden subnetworks [PDF]

Discrete Mathematics & Theoretical Computer Science, 2011
We are interested in fixed points in Boolean networks, $\textit{i.e.}$ functions $f$ from $\{0,1\}^n$ to itself. We define the subnetworks of $f$ as the restrictions of $f$ to the hypercubes contained in $\{0,1\}^n$, and we exhibit a class $\mathcal{F ...
Adrien Richard
doaj   +1 more source

Unimodality Problems in Ehrhart Theory

, 2017
Ehrhart theory is the study of sequences recording the number of integer points in non-negative integral dilates of rational polytopes. For a given lattice polytope, this sequence is encoded in a finite vector called the Ehrhart $h^*$-vector. Ehrhart $h^*
A. Stapledon, Adam McCabe, Akihiro Higashitani, Alexander Postnikov, C. Bey, C. Haase, Carla D. Savage, Carla D. Savage, Christos A. Athanasiadis, E. Ehrhart, E. Katz, Federico Ardila, Francesco Brenti, H. Ohsugi, Hidefumi Ohsugi, I.M. Gelfand, Jan Schepers, Jeffrey C. Lagarias, Jesús A. De Loera, Jesús A. De Loera, Joseph Gubeladze, M. Beck, M. Hochster, M. Kreuzer, M. Mustaţǎ, Maria Chudnovsky, Matthias Beck, Matthias Beck, Matthias Beck, Matthias Beck, Mireille Bousquet-Mélou, Mordechai Katzman, Neil L. White, P. McMullen, R.P. Stanley, RICHARD P. STANLEY, Richard P. Stanley, S. Payne, T. Hibi, T. Hibi, Tadahito Harima, Takayuki Hibi, Takayuki Hibi, Thomas Lam, V.V. Batyrev, Winfried Bruns   +45 more
core   +1 more source

Maximum Shattering

Journal of Combinatorial Designs, Volume 33, Issue 12, Page 456-470, December 2025.
ABSTRACT A family ℱ of subsets of [ n ] = { 1 , 2 , … , n } shatters a set A ⊆ [ n ] if for every A ′ ⊆ A, there is an F ∈ ℱ such that F ∩ A = A '. We develop a framework to analyze f ( n , k , d ), the maximum possible number of subsets of [ n ] of size d that can be shattered by a family of size k.
Noga Alon, Varun Sivashankar, Daniel G. Zhu   +2 more
wiley   +1 more source

Geometric combinatorics and computational molecular biology: branching polytopes for RNA sequences

, 2016
Questions in computational molecular biology generate various discrete optimization problems, such as DNA sequence alignment and RNA secondary structure prediction.
Drellich, Elizabeth, Gainer-Dewar, Andrew, Harrington, Heather A., He, Qijun, Heitsch, Christine, Poznanović, Svetlana   +5 more
core   +1 more source

Dominating K t‐Models

Journal of Graph Theory, Volume 110, Issue 4, Page 448-456, December 2025.
ABSTRACT A dominating K t‐model in a graph G is a sequence ( T 1 , … , T t ) of pairwise disjoint non‐empty connected subgraphs of G, such that for 1 ⩽ i < j ⩽ t every vertex in T j has a neighbour in T i. Replacing ‘every vertex in T j’ by ‘some vertex in T j’ retrieves the standard definition of K t‐model, which is equivalent to K t being a minor of ...
Freddie Illingworth, David R. Wood
wiley   +1 more source

Decomposition spaces in combinatorics [PDF]

, 2016
A decomposition space (also called unital 2-Segal space) is a simplicial object satisfying an exactness condition weaker than the Segal condition: just as the Segal condition expresses (up to homotopy) composition, the new condition expresses ...
Gálvez Carrillo, Maria Immaculada, Kock, Joachim, Tonks, Andrew   +2 more
core   +1 more source

Analyzing Boltzmann Samplers for Bose-Einstein Condensates with Dirichlet Generating Functions

, 2017
Boltzmann sampling is commonly used to uniformly sample objects of a particular size from large combinatorial sets. For this technique to be effective, one needs to prove that (1) the sampling procedure is efficient and (2) objects of the desired size ...
Bernstein, Megan, Fahrbach, Matthew, Randall, Dana   +2 more
core   +1 more source

Fast Construction on a Restricted Budget

Random Structures &Algorithms, Volume 67, Issue 4, December 2025.
ABSTRACT We introduce a model of a controlled random graph process. In this model, the edges of the complete graph Kn$$ {K}_n $$ are ordered randomly and then revealed, one by one, to a player called Builder. He must decide, immediately and irrevocably, whether to purchase each observed edge.
Alan Frieze, Michael Krivelevich, Peleg Michaeli   +2 more
wiley   +1 more source