Results 41 to 50 of about 156 (150)

Splines, lattice points, and (arithmetic) matroids [PDF]

open access: yesDiscrete Mathematics & Theoretical Computer Science, 2014
Let $X$ be a $(d \times N)$-matrix. We consider the variable polytope $\Pi_X(u) = \left\{ w \geq 0 : Xw = u \right\}$. It is known that the function $T_X$ that assigns to a parameter $u \in \mathbb{R}^N$ the volume of the polytope $\Pi_X(u)$ is piecewise
Matthias Lenz
doaj   +1 more source

The Chip Firing Game and Matroid Complexes [PDF]

open access: yesDiscrete 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
doaj   +1 more source

Tutte polynomial activities

open access: yes, 2022
18 pages, 6 figures. This is a draft of a chapter for the Handbook on the Tutte Polynomial. Comments are welcome!
openaire   +2 more sources

A study about the Tutte polynomials of benzenoid chains

open access: yesTopological Algebra and its Applications, 2017
The Tutte polynomials for signed graphs were introduced by Kauffman. In 2012, Fath-Tabar, Gholam-Rezaeı and Ashrafı presented a formula for computing Tutte polynomial of a benzenoid chain. From this point on, we have also calculated the Tutte polynomials
Sahin Abdulgani
doaj   +1 more source

Colored Tutte polynomials and composite knots [PDF]

open access: yesDiscrete Mathematics & Theoretical Computer Science, 2009
Surveying the results of three recent papers and some currently ongoing research, we show how a generalization of Brylawski's tensor product formula to colored graphs may be used to compute the Jones polynomial of some fairly complicated knots and, in ...
Gábor Hetyei   +2 more
doaj   +1 more source

Tutte polynomials for directed graphs

open access: yesJournal of Combinatorial Theory, Series B, 2020
The Tutte polynomial is a fundamental invariant of graphs. In this article, we define and study a generalization of the Tutte polynomial for directed graphs, that we name B-polynomial. The B-polynomial has three variables, but when specialized to the case of graphs (that is, digraphs where arcs come in pairs with opposite directions), one of the ...
Jordan Awan, Olivier Bernardi
openaire   +4 more sources

Tutte Polynomial of Multi-Bridge Graphs [PDF]

open access: yesComputer Science Journal of Moldova, 2013
In this paper, using a well-known recursion for computing the Tutte polynomial of any graph, we found explicit formulae for the Tutte polynomials of any multi-bridge graph and some $2-$tree graphs.
Julian A. Allagan
doaj  

Bijections for lattice paths between two boundaries [PDF]

open access: yesDiscrete Mathematics & Theoretical Computer Science, 2012
We prove that on the set of lattice paths with steps $N=(0,1)$ and $E=(1,0)$ that lie between two boundaries $B$ and $T$, the two statistics `number of $E$ steps shared with $B$' and `number of $E$ steps shared with $T$' have a symmetric joint ...
Sergi Elizalde, Martin Rubey
doaj   +1 more source

An inequality for Tutte polynomials [PDF]

open access: yesCombinatorica, 2010
The Tutte polynomial of the graph \(G=(V,E)\) can be defined by the closed formula \[ TG(x, y) =\sum_{A\subseteq E} (x - 1)^{r(E)-r(A)}(y - 1)^{| A| -r(A)} \] where \(r(A)=| V | -\omega (V,A)\), and \(\omega(V,A)\) denotes the number of components in the graph \((V,A)\). The author proves that, for a graph \(G\) without loops or bridges and \(a\), \(b\)
openaire   +2 more sources

Formulas for the computation of the Tutte polynomial of graphs with parallel classes

open access: yesElectronic Journal of Graph Theory and Applications, 2018
We give some reduction formulas for  computing the Tutte polynomial of any graph with parallel classes. Several examples are given to illustrate our results.
Eunice Mphako-Banda, Julian A. Allagan
doaj   +1 more source

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