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Related papers: Interlace Polynomials: Enumeration, Unimodality, a…

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We introduce a new graph polynomial in two variables. This ``interlace'' polynomial can be computed in two very different ways. The first is an expansion analogous to the state space expansion of the Tutte polynomial; the significant…

Combinatorics · Mathematics 2007-05-23 Richard Arratia , Bela Bollobas , Gregory B. Sorkin

We consider the multivariate interlace polynomial introduced by Courcelle (2008), which generalizes several interlace polynomials defined by Arratia, Bollobas, and Sorkin (2004) and by Aigner and van der Holst (2004). We present an…

Data Structures and Algorithms · Computer Science 2015-03-13 Markus Bläser , Christian Hoffmann

We obtain the following characterization of $Q$-polynomial distance-regular graphs. Let $\G$ denote a distance-regular graph with diameter $d\ge 3$. Let $E$ denote a minimal idempotent of $\G$ which is not the trivial idempotent $E_0$. Let…

Combinatorics · Mathematics 2009-08-31 Aleksandar Jurisic , Paul Terwilliger , Arjana Zitnik

A graph $G$ is well-covered if all its maximal stable sets have the same size, denoted by alpha(G) (M. D. Plummer, 1970). If for any $k$ the $k$-th coefficient of a polynomial I(G;x) is equal to the number of stable sets of cardinality $k$…

Combinatorics · Mathematics 2007-05-23 Vadim E. Levit , Eugen Mandrescu

Partial cubes are the graphs which can be embedded into hypercubes. The {\em cube polynomial} of a graph $G$ is a counting polynomial of induced hypercubes of $G$, which is defined as $C(G,x):=\sum_{i\geqslant 0}\alpha_i(G)x^i$, where…

Combinatorics · Mathematics 2024-06-18 Yan-Ting Xie , Yong-De Feng , Shou-Jun Xu

The domination polynomial of a graph $G$ is given by $D(G,x)=\sum_{k=0}^{n} d_k(G)x^k$ where $d_k(G)$ records the number of $k$-element dominating sets in $G$. A conjecture of Alikhani and Peng asserts that these polynomials have unimodal…

Combinatorics · Mathematics 2026-01-22 Mohamed Omar

The graph polynomial for the number of independent sets of size $k$ in a general undirected graph is shown to be equal to an elementary symmetric polynomial of the vertex monomials, which are determined by the edges incident at the…

Combinatorics · Mathematics 2023-12-12 R. L. Streit

Through a series of papers in the 1980's, Bouchet introduced isotropic systems and the Tutte-Martin polynomial of an isotropic system. Then, Arratia, Bollob\'as, and Sorkin developed the interlace polynomial of a graph in [ABS00] in…

Combinatorics · Mathematics 2007-05-23 Joanna A. Ellis-Monaghan , Irasema Sarmiento

There are local operators on (labeled) graphs $G$ with labels $(g_{ij})$ coming from a finite field. If the filed is binary, in other words, if the graph is ordinary, the operation is just the local complementation. That is, to choose a…

Combinatorics · Mathematics 2007-07-05 Mohsen Bahramgiri , Salman Beigi

In this paper, we survey results regarding the interlace polynomial of a graph, connections to such graph polynomials as the Martin and Tutte polynomials, and generalizations to the realms of isotropic systems and delta-matroids.

Combinatorics · Mathematics 2016-01-13 Ada Morse

This survey paper contains a tutorial introduction to distance-regular graphs, with an emphasis on the subconstituent algebra and the $Q$-polynomial property.

Combinatorics · Mathematics 2022-08-30 Paul Terwilliger

Let q be a power of a prime and E be an elliptic curve defined over F_q. In "Combinatorial aspects of elliptic curves" [17], the present author examined a sequence of polynomials which express the N_k's, the number of points on E over the…

Combinatorics · Mathematics 2007-10-03 Gregg Musiker

Inspired by the study of community structure in connection networks, we introduce the graph polynomial $Q(G;x,y)$, the bivariate generating function which counts the number of connected components in induced subgraphs. We give a recursive…

Combinatorics · Mathematics 2013-09-10 P. Tittmann , I. Averbouch , J. A. Makowsky

We take an elementary and systematic approach to the problem of extending the Tutte polynomial to the setting of embedded graphs. Four notions of embedded graphs arise naturally when considering deletion and contraction operations on graphs…

Combinatorics · Mathematics 2023-01-02 Stephen Huggett , Iain Moffatt

The intention of the paper is to move a step towards a classification of network topologies that exhibit periodic quantum dynamics. We show that the evolution of a quantum system, whose hamiltonian is identical to the adjacency matrix of a…

Quantum Physics · Physics 2007-05-23 Nitin Saxena , Simone Severini , Igor Shparlinski

The $Q$-polynomial property is an algebraic property of distance-regular graphs, that was introduced by Delsarte in his study of coding theory. Many distance-regular graphs admit the $Q$-polynomial property. Only recently the $Q$-polynomial…

Combinatorics · Mathematics 2024-04-22 Blas Fernández , Roghayeh Maleki , Štefko Miklavič , Giusy Monzillo

We investigate, using the notion of linear quotients, significative classes of connected graphs whose monomial edge ideals, not necessarily squarefree, have linear resolution, in order to compute standard algebraic invariants of the…

Rings and Algebras · Mathematics 2012-10-30 Maurizio Imbesi , Monica La Barbiera

We enumerate certain geometric equivalence classes of subgraphs induced by Hamiltonian paths and cycles in complete graphs. Said classes are orbits under the action of certain direct products of dihedral and cyclic groups on sets of strings…

Combinatorics · Mathematics 2021-08-31 Samuel Herman , Eirini Poimenidou

We study finite graphs embedded in oriented surfaces by associating a polynomial to it. The tools used in developing a theory of such graph polynomials are algebraic topological while the polynomial itself is inspired from ideas arising in…

Combinatorics · Mathematics 2022-05-02 Somnath Basu , Dhruv Bhasin , Siddhartha Lal , Siddhartha Patra

We study unmixed and Cohen-Macaulay properties of the binomial edge ideal of some classes of graphs. We compute the depth of the binomial edge ideal of a generalized block graph. We also characterize all generalized block graphs whose…

Commutative Algebra · Mathematics 2015-06-04 Dariush Kiani , Sara Saeedi Madani