## Search

Now showing items 1-10 of 13

#### Laplacian Eigenvectors of graphs

(Springer Verlag, 2007)

[No abstract available]

#### Semiregular trees with minimal Laplacian spectral radius

(Elsevier Inc, 2010-04-15)

A semiregular tree is a tree where all non-pendant vertices have the same degree. Among all semiregular trees with fixed order and degree, a graph with minimal (adjacency/Laplacian) spectral radius is a caterpillar. Counter ...

#### Graphs of given order and size and minimum algebraic connectivity

(Elsevier Science Inc, 2012-04-01)

The structure of connected graphs of given size and order that have minimal algebraic connectivity is investigated. It is shown that they must consist of a chain of cliques. Moreover, an upper bound for the number of maximal ...

#### Cryptanalysis of Fridrich's chaotic image encryption

(World Scientific Publishing, 2010-05)

We cryptanalyze Fridrich's chaotic image encryption algorithm. We show that the algebraic weaknesses of the algorithm make it vulnerable against chosen-ciphertext attacks. We propose an attack that reveals the secret ...

#### Four-cycled graphs with topological applications

(Birkhauser Verlag AG, 2012-03)

We call a simple graph G a 4-cycled graph if either it has no edges or every edge of it is contained in an induced 4-cycle of G. Our interest on 4-cycled graphs is motivated by the fact that their clique complexes play an ...

#### Graphs with given degree sequence and maximal spectral radius

(Electronic Journal of Combinatorics, 2008-09-15)

We describe the structure of those graphs that have largest spectral radius in the class of all connected graphs with a given degree sequence. We show that in such a graph the degree sequence is non-increasing with respect ...

#### Dendrimers are the unique chemical trees with maximum spectral radius

(Univ Kragujevac, 2012)

It is shown that dendrimers have maximum spectral radius and maximum Collatz-Sinogowitz index among all chemical trees of given size. The result is also generalized for the class of chemical trees with prescribed number ...

#### Some notes on spectra of cographs

(Charles Babbage Res Ctr, 2011-07)

A cograph is a P-4-free graph. We first give a short proof of the fact that 0 (-1) belongs to the spectrum of a connected cograph (with at least two vertices) if and only if it contains duplicate (resp. coduplicate) vertices. ...

#### Algebraic connectivity and degree sequences of trees

(Elsevier Science Inc, 2009-01-15)

We investigate the structure of trees that have minimal algebraic connectivity among all trees with a given degree sequence. We show that such trees are caterpillars and that the vertex degrees are non-decreasing on every ...

#### Largest eigenvalues of the discrete p-Laplacian of trees with degree sequences

(Int Linear Algebra Soc, 2009-03)

Trees that have greatest maximum p-Laplacian eigenvalue among all trees with a given degree sequence are characterized. It is shown that such extremal trees can be obtained by breadth-first search where the vertex degrees ...