Results 51 to 60 of about 70,151 (171)

Transforming Solutions for the Oberwolfach Problem into Solutions for the Spouse‐Loving Variant

open access: yesJournal of Combinatorial Designs, EarlyView.
ABSTRACT The Oberwolfach problem OP ( F ) $\mathrm{OP}(F)$, for a 2‐factor F $F$ of K n ${K}_{n}$, asks whether there exists a 2‐factorization of K n ${K}_{n}$ (if n $n$ is odd) or K n − I ${K}_{n}-I$ (if n $n$ is even) where each 2‐factor is isomorphic to F $F$. Here, I $I$ denotes any 1‐factor of K n ${K}_{n}$. For even n $n$, the problem OP( F ) $(F)
Maruša Lekše, Mateja Šajna
wiley   +1 more source

Analysis of an algorithm catching elephants on the Internet [PDF]

open access: yesDiscrete Mathematics & Theoretical Computer Science, 2008
The paper deals with the problem of catching the elephants in the Internet traffic. The aim is to investigate an algorithm proposed by Azzana based on a multistage Bloom filter, with a refreshment mechanism (called $\textit{shift}$ in the present paper),
Yousra Chabchoub   +3 more
doaj   +1 more source

On Strongly and Robustly Critical Graphs

open access: yesJournal of Graph Theory, EarlyView.
ABSTRACT In extremal combinatorics, it is common to focus on structures that are minimal with respect to a certain property. In particular, critical and list‐critical graphs occupy a prominent place in graph coloring theory. Stiebitz, Tuza, and Voigt introduced strongly critical graphs, i.e., graphs that are k $k$‐critical yet L $L$‐colorable with ...
Anton Bernshteyn   +3 more
wiley   +1 more source

Mixed Powers of Generating Functions [PDF]

open access: yesDiscrete Mathematics & Theoretical Computer Science, 2006
Given an integer $m \geq 1$, let $\| \cdot \|$ be a norm in $\mathbb{R}^{m+1}$ and let $\mathbb{S}_+^m$ denote the set of points $\mathbf{d}=(d_0,\ldots,d_m)$ in $\mathbb{R}^{m+1}$ with nonnegative coordinates and such that $\| \mathbf{d} \|=1$. Consider
Manuel Lladser
doaj   +1 more source

Combinatorics and Geometry of Transportation Polytopes: An Update [PDF]

open access: yes, 2013
A transportation polytope consists of all multidimensional arrays or tables of non-negative real numbers that satisfy certain sum conditions on subsets of the entries.
De Loera, Jesús A., Kim, Edward D.
core  

On Tight Tree‐Complete Hypergraph Ramsey Numbers

open access: yesJournal of Graph Theory, EarlyView.
ABSTRACT Chvátal showed that for any tree T $T$ with k $k$ edges, the Ramsey number R ( T , n ) = k ( n − 1 ) + 1 $R(T,n)=k(n-1)+1$. For r = 3 $r=3$ or 4, we show that, if T $T$ is an r $r$‐uniform nontrivial tight tree, then the hypergraph Ramsey number R ( T , n ) = Θ ( n r − 1 ) $R(T,n)={\rm{\Theta }}({n}^{r-1})$.
Jiaxi Nie
wiley   +1 more source

Extended Rate, more GFUN [PDF]

open access: yesDiscrete Mathematics & Theoretical Computer Science, 2006
We present a software package that guesses formulas for sequences of, for example, rational numbers or rational functions, given the first few terms.
Martin Rubey
doaj   +1 more source

Orientations of Graphs With at Most One Directed Path Between Every Pair of Vertices

open access: yesJournal of Graph Theory, EarlyView.
ABSTRACT Given a graph G $G$, we say that an orientation D $D$ of G $G$ is a KT orientation if, for all u , v ∈ V ( D ) $u,v\in V(D)$, there is at most one directed path (in any direction) between u $u$ and v $v$. Graphs that admit such orientations have been used to construct graphs with large chromatic number and small clique number that served as ...
Barbora Dohnalová   +3 more
wiley   +1 more source

The first ascent of size $d$ or more in compositions [PDF]

open access: yesDiscrete Mathematics & Theoretical Computer Science, 2006
A composition of a positive integer $n$ is a finite sequence of positive integers $a_1, a_2, \ldots, a_k$ such that $a_1+a_2+ \cdots +a_k=n$. Let $d$ be a fixed nonnegative integer.
Charlotte Brennan, Arnold Knopfmacher
doaj   +1 more source

Spaceborne and spaceborn: Physiological aspects of pregnancy and birth during interplanetary flight

open access: yesExperimental Physiology, EarlyView.
Abstract Crewed interplanetary return missions that are on the planning horizon will take years, more than enough time for initiation and completion of a pregnancy. Pregnancy is viewed as a sequence of processes – fertilization, blastocyst formation, implantation, gastrulation, placentation, organogenesis, gross morphogenesis, birth and neonatal ...
Arun V. Holden
wiley   +1 more source

Home - About - Disclaimer - Privacy