Results 31 to 40 of about 67 (66)
Signed Complete Graphs with Maximum Index
Discussiones Mathematicae Graph Theory, 2020 Let Γ = (G, σ) be a signed graph, where G is the underlying simple graph and σ E(G) → {−, +} is the sign function on the edges of G. The adjacency matrix of a signed graph has −1 or +1 for adjacent vertices, depending on the sign of the edges.
Akbari Saieed +3 more
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, 2023 “142nd Article” || Featured Tweets Available at @WordPress @Preprints_org @ResearchGate @Scribd @academia @ZENODO_ORG @Twitter @LinkedIn @Amazon @googlebooks @GooglePlay — “#142nd Article” || New Research On Cancer's Recognition and Neutrosophic ...
Henry Garrett
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On Regular Signed Graphs with Three Eigenvalues
Discussiones Mathematicae Graph Theory, 2020 In this paper our focus is on regular signed graphs with exactly 3 (distinct) eigenvalues. We establish certain basic results; for example, we show that they are walk-regular.
Anđelić Milica +2 more
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Balancedness and the Least Laplacian Eigenvalue of Some Complex Unit Gain Graphs
Discussiones Mathematicae Graph Theory, 2020 Let 𝕋4 = {±1, ±i} be the subgroup of 4-th roots of unity inside 𝕋, the multiplicative group of complex units. A complex unit gain graph Φ is a simple graph Γ = (V (Γ) = {v1, . . .
Belardo Francesco +2 more
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A note on the eigenvalue free intervals of some classes of signed threshold graphs
Special Matrices, 2019 We consider a particular class of signed threshold graphs and their eigenvalues. If Ġ is such a threshold graph and Q(Ġ ) is a quotient matrix that arises from the equitable partition of Ġ , then we use a sequence of elementary matrix operations to prove
Anđelić Milica +2 more
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Eigenpairs of adjacency matrices of balanced signed graphs
Special MatricesIn this article, we study eigenvalues λ\lambda and their associated eigenvectors xx of the adjacency matrices AA of balanced signed graphs. Balanced signed graphs were first introduced and studied by Harary to handle a problem in social psychology ...
Chen Mei-Qin
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Orientable ℤN-Distance Magic Graphs
Discussiones Mathematicae Graph Theory, 2019 Let G = (V, E) be a graph of order n. A distance magic labeling of G is a bijection ℓ: V → {1, 2, . . ., n} for which there exists a positive integer k such that ∑x∈N(v)ℓ(x) = k for all v ∈ V, where N(v) is the open neighborhood of v.
Cichacz Sylwia +2 more
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EURO Journal on Computational Optimization, 2017 One challenge for social network researchers is to evaluate balance in a social network. The degree of balance in a social group can be used as a tool to study whether and how this group evolves to a possible balanced state.
Mario Levorato +3 more
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Kontsevich's star-product up to order 7 for affine Poisson brackets: where are the Riemann zeta values? [PDF]
Open Communications in Nonlinear Mathematical PhysicsThe Kontsevich star-product admits a well-defined restriction to the class of affine -- in particular, linear -- Poisson brackets; its graph expansion consists only of Kontsevich's graphs with in-degree $\leqslant 1$ for aerial vertices.
Ricardo Buring, Arthemy V. Kiselev
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Signed graphs with strong (anti-)reciprocal eigenvalue property
Special MatricesA (signed) graph is said to exhibit the strong reciprocal (anti-reciprocal) eigenvalue property (SR) (resp., (-SR)) if for any eigenvalue λ\lambda , it has 1λ\frac{1}{\lambda } (resp.,−1λ-\frac{1}{\lambda }) as an eigenvalue as well, with the same ...
Belardo Francesco, Huntington Callum
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