Results 51 to 60 of about 38,730 (201)

Distance-Regular Graphs with Strongly Regular Subconstituents [PDF]

Journal of Algebraic Combinatorics, 1997
The main result of the article is a theorem about distance-regular graphs of diameter \(d\geq 3\) with all subconstituents being strongly regular graphs. The author shows that these are precisely the Taylor graphs \((d=3\) and \(|\Gamma_3 (u) |=1)\) or graphs with \(a_1= 0\), \(a_i\leq 1\) for \(2\leq i\leq d\).
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On Strongly Regular Graphs and the Friendship Theorem

Mathematics
This paper presents an alternative proof of the celebrated friendship theorem, originally established by Erdős, Rényi, and Sós in 1966. The proof relies on a closed-form expression for the Lovász ϑ-function of strongly regular graphs, recently derived by
Igal Sason
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On the locating matrix of a graph and its spectral analysis [PDF]

Computer Science Journal of Moldova, 2017
We introduce a new matrix representation for a graph by defining the locating matrix $\mathbf{Lo}(G)$ of $G$. We define the locating eigenvalues, the locating spectrum, and locating energy of the graph and we calculate them for some standard graphs.
H. N. Ramaswamy, Anwar Alwardi, N. Ravi Kumar   +2 more
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θ-regular spaces

International Journal of Mathematics and Mathematical Sciences, 1985
In this paper we define a topological space X to be θ-regular if every filterbase in X with a nonempty θ-adherence has a nonempty adherence. It is shown that the class of θ-regular topological spaces includes rim-compact topological spaces and that θ ...
Dragan S. Janković
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rc-continuous functions and functions with rc-strongly closed graph

International Journal of Mathematics and Mathematical Sciences, 2003
The family of regular closed subsets of a topological space is used to introduce two concepts concerning a function f from a space X to a space Y. The first of them is the notion of f being rc-continuous.
Bassam Al-Nashef
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Non-existence of quasi-symmetric designs having certain pseudo-geometric block graphs

AKCE International Journal of Graphs and Combinatorics
The block graph of a quasi-symmetric design is strongly regular. It is a challenging problem to decide which strongly regular graphs are block graphs of quasi-symmetric designs.
Kusum S. Rajbhar, Rajendra M. Pawale
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Fault-tolerant quantum speedup from constant depth quantum circuits

Physical Review Research, 2020
A defining feature in the field of quantum computing is the potential of a quantum device to outperform its classical counterpart for a specific computational task.
Rawad Mezher, Joe Ghalbouni, Joseph Dgheim, Damian Markham   +3 more
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More two-distance counterexamples to Borsuk's conjecture from strongly regular graphs [PDF]

, 2020
Thomas Jenrich
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Random strongly regular graphs? [PDF]

Electronic Notes in Discrete Mathematics, 2001
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
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Hemisystems and strongly regular graphs

Discrete Applied Mathematics
In a recent paper, it was constructed a family of hemisystems of H(3,p2), for every prime p of the form p=1+4a2, stabilised by PSL(2,p)×C[Formula presented]. In the case p=5, the full automorphism group is 3.A7, and the hemisystem is isomorphic to a sporadic one described by A. Cossidente and T. Penttila in 2005.
Pallozzi Lavorante V., Romaniello F., Smaldore V.   +2 more
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