Results 21 to 30 of about 855 (105)
More Aspects of Arbitrarily Partitionable Graphs
Discussiones Mathematicae Graph Theory, 2022 A graph G of order n is arbitrarily partitionable (AP) if, for every sequence (n1, . . ., np) partitioning n, there is a partition (V1, . . ., ,Vp) of V (G) such that G[Vi] is a connected ni-graph for i = 1, . . ., p.
Bensmail Julien, Li Binlong
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The hidden symmetry of Kontsevich's graph flows on the spaces of Nambu-determinant Poisson brackets [PDF]
Open Communications in Nonlinear Mathematical Physics, 2022 Kontsevich's graph flows are -- universally for all finite-dimensional affine Poisson manifolds -- infinitesimal symmetries of the spaces of Poisson brackets.
Ricardo Buring +2 more
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Non-Solvable Spaces of Linear Equation Systems [PDF]
, 2012 Different from the homogenous systems, a Smarandache system is a contradictory system in which an axiom behaves in at least two different ways within the same system, i.e., validated and invalided, or only invalided but in multiple distinct ...
Mao, Linfan
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Injectivity results for coarse homology theories
Proceedings of the London Mathematical Society, Volume 121, Issue 6, Page 1619-1684, December 2020., 2020 Abstract We show injectivity results for assembly maps using equivariant coarse homology theories with transfers. Our method is based on the descent principle and applies to a large class of linear groups or, more generally, groups with finite decomposition complexity.
Ulrich Bunke +3 more
wiley +1 more source
Trees Whose Even-Degree Vertices Induce a Path are Antimagic
Discussiones Mathematicae Graph Theory, 2022 An antimagic labeling of a connected graph G is a bijection from the set of edges E(G) to {1, 2, . . ., |E(G)|} such that all vertex sums are pairwise distinct, where the vertex sum at vertex v is the sum of the labels assigned to edges incident to v.
Lozano Antoni +3 more
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Homotopy type of the complex of free factors of a free group
Proceedings of the London Mathematical Society, Volume 121, Issue 6, Page 1737-1765, December 2020., 2020 Abstract We show that the complex of free factors of a free group of rank n⩾2 is homotopy equivalent to a wedge of spheres of dimension n−2. We also prove that for n⩾2, the complement of (unreduced) Outer space in the free splitting complex is homotopy equivalent to the complex of free factor systems and moreover is (n−2)‐connected.
Benjamin Brück, Radhika Gupta
wiley +1 more source
An on-line competitive algorithm for coloring bipartite graphs without long induced paths [PDF]
, 2015 The existence of an on-line competitive algorithm for coloring bipartite graphs remains a tantalizing open problem. So far there are only partial positive results for bipartite graphs with certain small forbidden graphs as induced subgraphs. We propose a
Micek, Piotr, Wiechert, Veit
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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
On the Optimality of 3-Restricted Arc Connectivity for Digraphs and Bipartite Digraphs
Discussiones Mathematicae Graph Theory, 2022 Let D be a strong digraph. An arc subset S is a k-restricted arc cut of D if D − S has a strong component D′ with order at least k such that D\V (D′) contains a connected subdigraph with order at least k.
Zhang Yaoyao, Meng Jixiang
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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