Results 11 to 20 of about 99 (66)
α‐Completely Regular and Almost α‐Completely Regular Spaces
Mathematical Problems in Engineering, Volume 2022, Issue 1, 2022., 2022 This work is aimed at studying some of the characterizations of α‐completely regular and almost α‐completely regular spaces through the new concept of α‐zero sets and α‐continuous functions. 2010 Mathematics Subject Classification: primary 05C38, 15A15; Secondary 05A15, 15A18.
A.A. Azzam, A.A. Nasef, Cenap Özel
wiley +1 more source
When products of projections diverge
Journal of the London Mathematical Society, Volume 102, Issue 1, Page 345-367, August 2020., 2020 Abstract Slow convergence of cyclic projections implies divergence of random projections and vice versa. Let L1,L2,⋯,LK be a family of K closed subspaces of a Hilbert space. It is well known that although the cyclic product of the orthogonal projections on these spaces always converges in norm, random products might diverge.
Eva Kopecká
wiley +1 more source
Decomposing tournaments into paths
Proceedings of the London Mathematical Society, Volume 121, Issue 2, Page 426-461, August 2020., 2020 Abstract We consider a generalisation of Kelly's conjecture which is due to Alspach, Mason, and Pullman from 1976. Kelly's conjecture states that every regular tournament has an edge decomposition into Hamilton cycles, and this was proved by Kühn and Osthus for large tournaments. The conjecture of Alspach, Mason, and Pullman asks for the minimum number
Allan Lo +3 more
wiley +1 more source
Alternating-Pancyclism in 2-Edge-Colored Graphs
Discussiones Mathematicae Graph Theory, 2021 An alternating cycle in a 2-edge-colored graph is a cycle such that any two consecutive edges have different colors. Let G1, . . ., Gkbe a collection of pairwise vertex disjoint 2-edge-colored graphs. The colored generalized sum of G1, . . ., Gk, denoted
Cordero-Michel Narda +1 more
doaj +1 more source
Path homology theory of edge-colored graphs
Open Mathematics, 2021 In this paper, we introduce the category and the homotopy category of edge-colored digraphs and construct the functorial homology theory on the foundation of the path homology theory provided by Grigoryan, Muranov, and Shing-Tung Yau.
Muranov Yuri V., Szczepkowska Anna
doaj +1 more source
On the Independence Number of Traceable 2-Connected Claw-Free Graphs
Discussiones Mathematicae Graph Theory, 2019 A well-known theorem by Chvátal-Erdőos [A note on Hamilton circuits, Discrete Math. 2 (1972) 111–135] states that if the independence number of a graph G is at most its connectivity plus one, then G is traceable.
Wang Shipeng, Xiong Liming
doaj +1 more source
Forbidden Subgraphs for Existences of (Connected) 2-Factors of a Graph
Discussiones Mathematicae Graph Theory, 2023 Clearly, having a 2-factor in a graph is a necessary condition for a graph to be hamiltonian, while having an even factor in graph is a necessary condition for a graph to have a 2-factor.
Yang Xiaojing, Xiong Liming
doaj +1 more source
The Dichromatic Number of Infinite Families of Circulant Tournaments
Discussiones Mathematicae Graph Theory, 2017 The dichromatic number dc(D) of a digraph D is defined to be the minimum number of colors such that the vertices of D can be colored in such a way that every chromatic class induces an acyclic subdigraph in D.
Javier Nahid, Llano Bernardo
doaj +1 more source
Forbidden Subgraphs for Collapsible Graphs and Supereulerian Graphs
Discussiones Mathematicae Graph Theory, 2022 In this paper, we completely characterize the connected forbidden subgraphs and pairs of connected forbidden subgraphs that force a 2-edge-connected (2-connected) graph to be collapsible.
Liu Xia, Xiong Liming
doaj +1 more source
Labeled Packing of Cycles and Circuits
Discussiones Mathematicae Graph Theory, 2022 In 2013, Duchçne, Kheddouci, Nowakowski and Tahraoui introduced a labeled version of the graph packing problem. It led to the introduction of a new graph parameter, the k-packing label-span λk.
Joffard Alice, Kheddouci Hamamache
doaj +1 more source