Results 1 to 10 of about 1,481 (47)
Vertices with the Second Neighborhood Property in Eulerian Digraphs
, 2014 The Second Neighborhood Conjecture states that every simple digraph has a vertex whose second out-neighborhood is at least as large as its first out-neighborhood, i.e. a vertex with the Second Neighborhood Property.
Dong-Lan Luo (608306) +8 more
core +4 more sources
Hamilton decompositions of regular expanders: applications [PDF]
, 2012 In a recent paper, we showed that every sufficiently large regular digraph G on n vertices whose degree is linear in n and which is a robust outexpander has a decomposition into edge-disjoint Hamilton cycles.
Alon +42 more
core +6 more sources
Switching Reconstruction of Digraphs [PDF]
, 2013 Switching about a vertex in a digraph means to reverse the direction of every edge incident with that vertex. Bondy and Mercier introduced the problem of whether a digraph can be reconstructed up to isomorphism from the multiset of isomorphism types of ...
McKay, Brendan D., Schweitzer, Pascal
core +3 more sources
The conjugacy problem for automorphism groups of countable homogeneous structures [PDF]
, 2016 We consider the conjugacy problem for the automorphism groups of a number of countable homogeneous structures.
Coskey, Samuel, Ellis, Paul
core +3 more sources
Hitting minors, subdivisions, and immersions in tournaments
, 2018 The Erd\H{o}s-P\'osa property relates parameters of covering and packing of combinatorial structures and has been mostly studied in the setting of undirected graphs.
Raymond, Jean-Florent
core +3 more sources
, 2018 In 1995, Stiebitz asked the following question: For any positive integers $s,t$, is there a finite integer $f(s,t)$ such that every digraph $D$ with minimum out-degree at least $f(s,t)$ admits a bipartition $(A, B)$ such that $A$ induces a subdigraph ...
Bai, Yandong +3 more
core +1 more source
Oriented coloring on recursively defined digraphs
, 2019 Coloring is one of the most famous problems in graph theory. The coloring problem on undirected graphs has been well studied, whereas there are very few results for coloring problems on directed graphs. An oriented k-coloring of an oriented graph G=(V,A)
Gurski, Frank +2 more
core +1 more source
Local Out-Tournaments with Upset Tournament Strong Components I: Full and Equal {0,1}-Matrix Ranks [PDF]
, 2010 A digraph D is a local out-tournament if the outset of every vertex is a tournament. Here, we use local out-tournaments, whose strong components are upset tournaments, to explore the corresponding ranks of the adjacency matrices.
Derby, Jason M. +2 more
core +1 more source
Countable connected-homogeneous digraphs [PDF]
, 2013 A digraph is connected-homogeneous if every isomorphism between two finite connected induced subdigraphs extends to an automorphism of the whole digraph.
Hamann, Matthias
core
Priors on exchangeable directed graphs
, 2016 Directed graphs occur throughout statistical modeling of networks, and exchangeability is a natural assumption when the ordering of vertices does not matter.
Ackerman, Nathanael +2 more
core +1 more source