Results 31 to 40 of about 335 (183)
$Star^1$-convex functions on tropical linear spaces of complete graphs [PDF]
Discrete Mathematics & Theoretical Computer Science, 2012 Given a fan $\Delta$ and a cone $\sigma \in \Delta$ let $star^1(\sigma )$ be the set of cones that contain $\sigma$ and are one dimension bigger than $\sigma$ . In this paper we study two cones of piecewise linear functions defined on $\delta$ : the cone
Laura Escobar
doaj +1 more source
European Journal of Combinatorics, 2017 A laminar family is a collection $\mathscr{A}$ of subsets of a set $E$ such that, for any two intersecting sets, one is contained in the other. For a capacity function $c$ on $\mathscr{A}$, let $\mathscr{I}$ be $\{I:|I\cap A| \leq c(A)\text{ for all $A\in\mathscr{A}$}\}$.
Tara Fife, James G. Oxley
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Reducing the rank of a matroid [PDF]
Discrete Mathematics & Theoretical Computer Science, 2015 We consider the rank reduction problem for matroids: Given a matroid $M$ and an integer $k$, find a minimum size subset of elements of $M$ whose removal reduces the rank of $M$ by at least $k$. When $M$ is a graphical matroid this problem is the minimum $
Gwenaël Joret, Adrian Vetta
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Graphic Splitting of Cographic Matroids
Discussiones Mathematicae Graph Theory, 2015 In this paper, we obtain a forbidden minor characterization of a cographic matroid M for which the splitting matroid Mx,y is graphic for every pair x, y of elements of M.
Pirouz Naiyer
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Matroids on the Bases of Simple Matroids
European Journal of Combinatorics, 1981 Let M be a simple matroid (= combinatorial geometry). On the bases of M we consider two matroids S(M, F) and H(M, F), which depend on a field F. S(M, F) is the simplicial matroid with coefficients in F on the bases of M considered as simplices. H(M, F) has been studied by Björner in [1].
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A characterization of the base-matroids of a graphic matroid
Contributions to Discrete Mathematics, 2010 Let M=(E,F) be a matroid on a set E and B one of its bases. A closed set θ⊆E is saturated with respect to B when |θ∩B|≤r(θ), where r(θ) is the rank of θ. The collection of subsets I of E such that |I∩θ|≤r(θ) for every closed saturated set θ turns out to be the family of independent sets of a new matroid on E, called base-matroid and denoted by MB.
MAFFIOLI, FRANCESCO, ZAGAGLIA, NORMA
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Matroids on convex geometries (cg-matroids)
Discrete Mathematics, 2007 zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Satoru Fujishige +2 more
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The Chip Firing Game and Matroid Complexes [PDF]
Discrete Mathematics & Theoretical Computer Science, 2001 In this paper we construct from a cographic matroid M, a pure multicomplex whose degree sequence is the h―vector of the the matroid complex of M. This result provesa conjecture of Richard Stanley [Sta96] in the particular case of cographic matroids.
Criel Merino
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Edge‐Length Preserving Embeddings of Graphs Between Normed Spaces
Journal of Graph Theory, Volume 112, Issue 4, Page 491-506, August 2026.ABSTRACT The concept of graph embeddability, initially formalized by Belk and Connelly and later expanded by Sitharam and Willoughby, extends the question of embedding finite metric spaces into a given normed space. A finite simple graph G = ( V , E ) is said to be ( X , Y )‐embeddable if any set of induced edge lengths from an embedding of G into a ...
Sean Dewar +3 more
wiley +1 more source
When is the graph of a random 0/1 polytope a clique?
Bulletin of the London Mathematical Society, Volume 58, Issue 8, August 2026.Abstract We study graph‐theoretic properties of random 0/1$0/1$ polytopes. Specifically, let Qpn⊆{0,1}n$Q_p^n \subseteq \lbrace 0,1\rbrace ^n$ be a random subset where each point is included independently with probability p$p$, and consider the graph Gp$G_p$ of the polytope conv(Qpn)$\operatorname{conv}(Q_p^n)$.
Catherine Babecki +2 more
wiley +1 more source