Results 51 to 60 of about 504 (100)
Degree Subtraction Adjacency Eigenvalues and Energy of Graphs Obtained From Regular Graphs
Open Journal of Discrete Applied Mathematics, 2018 Let V (G) = {v1, v2, . . . , vn} be the vertex set of G and let dG(vi) be the degree of a vertex vi in G. The degree subtraction adjacency matrix of G is a square matrix DSA(G) = [dij ], in which dij = dG(vi) − dG(vj), if vi is adjacent to vj and dij = 0,
H. Ramane, Hemaraddi N. Maraddi
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The Wiener and Terminal Wiener indices of trees [PDF]
, 2013 Heydari \cite{heydari2013} presented very nice formulae for the Wiener and terminal Wiener indices of generalized Bethe trees. It is pity that there are some errors for the formulae.
Chen, Ya-Hong, Zhang, Xiao-Dong
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A Constructive Extension of the Characterization on Potentially Ks,t-Bigraphic Pairs
Discussiones Mathematicae Graph Theory, 2017 Let Ks,t be the complete bipartite graph with partite sets of size s and t. Let L1 = ([a1, b1], . . . , [am, bm]) and L2 = ([c1, d1], . . . , [cn, dn]) be two sequences of intervals consisting of nonnegative integers with a1 ≥ a2 ≥ . . . ≥ am and c1 ≥ c2
Guo Ji-Yun, Yin Jian-Hua
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Discussiones Mathematicae Graph Theory, 2018 A digraph is called irregular if its distinct vertices have distinct degree pairs. An irregular digraph is called minimal (maximal) if the removal of any arc (addition of any new arc) results in a non-irregular digraph. It is easily seen that the minimum
Górska Joanna +4 more
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The Bipartite-Splittance of a Bipartite Graph
Discussiones Mathematicae Graph Theory, 2019 A bipartite-split graph is a bipartite graph whose vertex set can be partitioned into a complete bipartite set and an independent set. The bipartite- splittance of an arbitrary bipartite graph is the minimum number of edges to be added or removed in ...
Yin Jian-Hua, Guan Jing-Xin
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Irreversible 2-conversion set in graphs of bounded degree [PDF]
Discrete Mathematics & Theoretical Computer Science, 2017 An irreversible $k$-threshold process (also a $k$-neighbor bootstrap percolation) is a dynamic process on a graph where vertices change color from white to black if they have at least $k$ black neighbors. An irreversible $k$-conversion set of a graph $G$
Jan Kynčl +2 more
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New Formulae for the Decycling Number of Graphs
Discussiones Mathematicae Graph Theory, 2019 A set S of vertices of a graph G is called a decycling set if G−S is acyclic. The minimum order of a decycling set is called the decycling number of G, and denoted by ∇(G). Our results include: (a) For any graph G,, where T is taken over all the spanning
Yang Chao, Ren Han
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Sombor index of zero-divisor graphs of commutative rings
Analele Stiintifice ale Universitatii Ovidius Constanta: Seria Matematica, 2022 In this paper, we investigate the Sombor index of the zero-divisor graph of ℤn which is denoted by Γ(ℤn) for n ∈ {pα, pq, p2q, pqr} where p, q and r are distinct prime numbers. Moreover, we introduce an algorithm which calculates the Sombor index of Γ(ℤn)
Gürsoy Arif +2 more
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ON ZAGREB INDICES AND ECCENTRIC CONNECTIVITY INDEX OF CERTAIN THORN GRAPHS
, 2016 The first three Zagreb indices of a graph G denoted, M1(G),M2(G) and M3(G), are well known. Equally well known is the eccentricity connectivity index denoted, ξ(G).
U. Mary +4 more
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The Subset-Strong Product of Graphs
Annales Mathematicae SilesianaeIn this paper, we introduce the subset-strong product of graphs and give a method for calculating the adjacency spectrum of this product. In addition, exact expressions for the first and second Zagreb indices of the subset-strong products of two graphs ...
Eliasi Mehdi
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