Results 31 to 40 of about 370,627 (270)
On the structure of compact graphs [PDF]
A simple graph \(G\) is called a compact graph if \(G\) contains no isolated vertices and for each pair \(x\), \(y\) of non-adjacent vertices of \(G\), there is a vertex \(z\) with \(N(x)\cup N(y)\subseteq N(z)\), where \(N(v)\) is the neighborhood of ...
Reza Nikandish, Farzad Shaveisi
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Walk entropies on graphs [PDF]
Entropies based on walks on graphs and on their line-graphs are defined. They are based on the summation over diagonal and off-diagonal elements of the thermal Green’s function of a graph also known as the communicability. The walk entropies are strongly
de la Peña, José A. +2 more
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Generation of strongly regular graphs from quaternary complex Hadamard matrices
A strongly regular graph with parameters (v, k, μ, λ) is a regular graph G with v vertices and k degree in which every two adjacent vertices have λ common neighbors and every two non-adjacent vertices have μ common neighbors. In this paper, we propose an
W. V. Nishadi +3 more
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Graph isomorphism and Gaussian boson sampling
We introduce a connection between a near-term quantum computing device, specifically a Gaussian boson sampler, and the graph isomorphism problem. We propose a scheme where graphs are encoded into quantum states of light, whose properties are then probed ...
Brádler Kamil +4 more
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On strictly Deza graphs with parameters (n,k,k-1,a) [PDF]
A nonempty $k$-regular graph $\Gamma$ on $n$ vertices is called a Deza graph if there exist constants $b$ and $a$ $(b \geq a)$ such that any pair of distinct vertices of $\Gamma$ has precisely either $b$ or $a$ common neighbours. The quantities $n$, $k$,
Kabanov, V. V. +2 more
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The Strongly Regular $(45,12,3,3)$ Graphs [PDF]
Using two backtrack algorithms based on different techniques, designed and implemented independently, we were able to determine up to isomorphism all strongly regular graphs with parameters $v=45$, $k=12$, $\lambda=\mu=3$. It turns out that there are $78$ such graphs, having automorphism groups with sizes ranging from $1$ to $51840$.
Coolsaet, K., Degraer, J., Spence, E.
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Observations on the Lovász θ-Function, Graph Capacity, Eigenvalues, and Strong Products
This paper provides new observations on the Lovász θ-function of graphs. These include a simple closed-form expression of that function for all strongly regular graphs, together with upper and lower bounds on that function for all regular graphs.
Igal Sason
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Translation from Discrete Math. 13, 357-381 (1975; Zbl 0311.05122).
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On the construction and comparison of graph irregularity indices [PDF]
Irregularity indices are generally used for quantitative characterization of topological structure of non-regular graphs. According to a widely accepted preconception, using a topological invariant (called a graph irregularity index) for that purpose ...
Réti Tamás, Tóth-Laufer Edit
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Automorphism groups of the constituent graphs of integral distance graphs
In this paper, we consider the automorphism groups of Cayley graphs which are a basis of a complete Boolean algebra of strongly regular graphs, one of such graph is the integral distance graph [Formula: see text] The automorphism groups of the integral ...
O. Habineza, E. Mwambene
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