Results 1 to 10 of about 3,890,729 (139)
On the diameter of an ideal [PDF]
Journal of Algebra, 2017 We begin the study of the notion of diameter of an ideal I of a polynomial ring S over a field, an invariant measuring the distance between the minimal primes of I. We provide large classes of Hirsch ideals, i.e.
Di Marca, Michela, Varbaro, Matteo
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Solar Physics, 1983 AbstractBecause of the renewed attention now paid to the solar diameter, its variations from equator to pole, or its secular or long-period changes, the question: what is a solar diameter? is not meaningless. Two kinds of definitions may be given: either astrophysical, each one relating to a specific physical parameter, or observational, relating to a ...
J. Rösch, R. Yerle
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Eigenvalues and the diameter of graphs [PDF]
Linear and Multilinear Algebra, 1995 Using eigenvalue interlacing and Chebyshev polynomials we find upper bounds for the diameter of regular and bipartite biregular graphs in terms of their eigenvalues. This improves results of Chung and Delorme and Sole. The same method gives upper bounds for the number of vertices at a given minimum distance from a given vertex set.
van Dam, E.R., Haemers, W.H.
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The diameter of associahedra [PDF]
Advances in Mathematics, 2014 It is proven here that the diameter of the d-dimensional associahedron is 2d-4 when d is greater than 9. Two maximally distant vertices of this polytope are explicitly described as triangulations of a convex polygon, and their distance is obtained using combinatorial arguments.
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Diameter Bounds for Planar Graphs [PDF]
, 2010 The inverse degree of a graph is the sum of the reciprocals of the degrees of its vertices. We prove that in any connected planar graph, the diameter is at most 5/2 times the inverse degree, and that this ratio is tight.
Fulek, Radoslav +2 more
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Oriented diameter of graphs with diameter 3
Journal of Combinatorial Theory, Series B, 2010 AbstractIn 1978, Chvátal and Thomassen proved that every 2-edge-connected graph with diameter 2 has an orientation with diameter at most 6. They also gave general bounds on the smallest value f(d) such that every 2-edge-connected graph G with diameter d has an orientation with diameter at most f(d). For d=3, their general bounds reduce to 8⩽f(3)⩽24. We
Qi Liu, Douglas B. West, Peter K. Kwok
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On Strong Diameter Padded Decompositions [PDF]
, 2019 Given a weighted graph G=(V,E,w), a partition of V is Delta-bounded if the diameter of each cluster is bounded by Delta. A distribution over Delta-bounded partitions is a beta-padded decomposition if every ball of radius gamma Delta is contained in a ...
Filtser, Arnold
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Diameters and Eigenvalues [PDF]
Journal of the American Mathematical Society, 1989 We derive a new upper bound for the diameter of a k k -regular graph G G as a function of the eigenvalues of the adjacency matrix. Namely, suppose the adjacency matrix of G G has eigenvalues λ 1 , λ
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Symmetric strong diameter two property [PDF]
, 2018 We study Banach spaces with the property that, given a finite number of slices of the unit ball, there exists a direction such that all these slices contain a line segment of length almost 2 in this direction.
Haller, Rainis +3 more
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The (a,b,s,t)-diameter of graphs: a particular case of conditional diameter [PDF]
, 2006 The conditional diameter of a connected graph $\Gamma=(V,E)$ is defined as follows: given a property ${\cal P}$ of a pair $(\Gamma_1, \Gamma_2)$ of subgraphs of $\Gamma$, the so-called \emph{conditional diameter} or ${\cal P}$-{\em diameter} measures the
Balbuena +10 more
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