Results 31 to 40 of about 155 (146)
Untwisting 3‐strand torus knots
Abstract We prove that the signature bound for the topological 4‐genus of 3‐strand torus knots is sharp, using McCoy's twisting method. We also show that the bound is off by at most 1 for 4‐strand and 6‐strand torus knots, and improve the upper bound on the asymptotic ratio between the topological 4‐genus and the Seifert genus of torus knots from 2/3 ...
S. Baader, I. Banfield, L. Lewark
wiley +1 more source
On q-Power Cycles in Cubic Graphs
In the context of a conjecture of Erdős and Gyárfás, we consider, for any q ≥ 2, the existence of q-power cycles (i.e., with length a power of q) in cubic graphs. We exhibit constructions showing that, for every q ≥ 3, there exist arbitrarily large cubic
Bensmail Julien
doaj +1 more source
On the Optimality of 3-Restricted Arc Connectivity for Digraphs and Bipartite Digraphs
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
doaj +1 more source
Location of zeros for the partition function of the Ising model on bounded degree graphs
Abstract The seminal Lee–Yang theorem states that for any graph the zeros of the partition function of the ferromagnetic Ising model lie on the unit circle in C. In fact, the union of the zeros of all graphs is dense on the unit circle. In this paper, we study the location of the zeros for the class of graphs of bounded maximum degree d⩾3, both in the ...
Han Peters, Guus Regts
wiley +1 more source
On Conditional Connectivity of the Cartesian Product of Cycles
The conditional h-vertex (h-edge) connectivity of a connected graph H of minimum degree k > h is the size of a smallest vertex (edge) set F of H such that H − F is a disconnected graph of minimum degree at least h. Let G be the Cartesian product of r ≥ 1
Saraf J.B., Borse Y.M., Mundhe Ganesh
doaj +1 more source
Algorithms for minimum flows [PDF]
We present a generic preflow algorithm and several implementations of it, that solve the minimum flow problem in O(n2m) time.
Eleonor Ciurea, Laura Ciupal
doaj
Classification of Filiform Lie Algebras up to dimension 7 Over Finite Fields
This paper tries to develop a recent research which consists in using Discrete Mathematics as a tool in the study of the problem of the classification of Lie algebras in general, dealing in this case with filiform Lie algebras up to dimension 7 over ...
Falcón Óscar J. +4 more
doaj +1 more source
Annular and pants thrackles [PDF]
A thrackle is a drawing of a graph in which each pair of edges meets precisely once. Conway's Thrackle Conjecture asserts that a thrackle drawing of a graph on the plane cannot have more edges than vertices.
Grace Misereh, Yuri Nikolayevsky
doaj +1 more source
Hardness Results and Spectral Techniques for Combinatorial Problems on Circulant Graphs [PDF]
We show that computing (and even approximating) MAXIMUM CLIQUE and MINIMUM GRAPH COLORING for circulant graphs is essentially as hard as in the general case.
Ivan Gerace +8 more
core +1 more source
Structural Properties of Recursively Partitionable Graphs with Connectivity 2
A connected graph G is said to be arbitrarily partitionable (AP for short) if for every partition (n1, . . . , np) of |V (G)| there exists a partition (V1, . . . , Vp) of V (G) such that each Vi induces a connected subgraph of G on ni vertices.
Baudon Olivier +3 more
doaj +1 more source

