Results 21 to 30 of about 234 (95)
Stability for the Erdős-Rothschild problem
Forum of Mathematics, Sigma, 2023 Given a sequence $\boldsymbol {k} := (k_1,\ldots ,k_s)$ of natural numbers and a graph G, let $F(G;\boldsymbol {k})$ denote the number of colourings of the edges of G with colours $1,\dots ,s$ , such that, for every $c \in \{1 ...
Oleg Pikhurko, Katherine Staden
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A STUDY OF INERTIA INDICES, SIGNATURE AND NULLITY OF V-PHENYLENIC $[m,n]$
, 2020 A molecular/chemical graph is hydrogen depleted chemical structure in which vertices denote atoms and edges denote the bonds. Topological descriptors are the numerical indices based on the topology of the atoms and their bonds (chemical conformation ...
Zheng-Qing Chu +3 more
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Comparing Eccentricity-Based Graph Invariants
Discussiones Mathematicae Graph Theory, 2020 The first and second Zagreb eccentricity indices (EM1 and EM2), the eccentric distance sum (EDS), and the connective eccentricity index (CEI) are all recently conceived eccentricity-based graph invariants, some of which found applications in chemistry ...
Hua Hongbo, Wang Hongzhuan, Gutman Ivan
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Some inequalities for the multiplicative sum Zagreb index of graph operations
, 2015 The multiplicative sum Zagreb index is defined for a simple graph G as the product of the terms dG(u)+dG(v) over all edges uv∈E(G) , where dG(u) denotes the degree of the vertex u of G .
M. Azari, A. Iranmanesh
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EXTREMAL UNICYCLIC GRAPHS WITH RESPECT TO ADDITIVELY WEIGHTED HARARY INDEX [PDF]
, 2013 In this paper we define cycle-star graphCSk;n k to be a graph onn vertices consisting of the cycle of lengthk andn k leafs appended to the same vertex of the cycle.
J. Sedlar
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Algorithms for minimum flows [PDF]
Computer Science Journal of Moldova, 2001 We present a generic preflow algorithm and several implementations of it, that solve the minimum flow problem in O(n2m) time.
Eleonor Ciurea, Laura Ciupal
doaj
Hyper-Wiener indices of polyphenyl chains and polyphenyl spiders
Open Mathematics, 2019 Let G be a connected graph and u and v two vertices of G. The hyper-Wiener index of graph G is WW(G)=12∑u,v∈V(G)(dG(u,v)+dG2(u,v))$\begin{array}{} WW(G)=\frac{1}{2}\sum\limits_{u,v\in V(G)}(d_{G}(u,v)+d^{2}_{G}(u,v)) \end{array}$, where dG(u, v) is the ...
Wu Tingzeng, Lü Huazhong
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A note on the k‐domination number of a graph
International Journal of Mathematics and Mathematical Sciences, Volume 13, Issue 1, Page 205-206, 1990., 1989 The k‐domination number of a graph G = G(V, E), γk(G), is the least cardinality of a set X ⊂ V such that any vertex in VX is adjacent to at least k vertices of X. Extending a result of Cockayne, Gamble and Shepherd [4], we prove that if , n ≥ 1, k ≥ 1 then, , where p is the order of G.
Y. Caro, Y. Roditty
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On the discrepancy of coloring finite sets
International Journal of Mathematics and Mathematical Sciences, Volume 13, Issue 4, Page 825-827, 1990., 1990 Given a subset S of {1, …, n} and a map X : {1, …, n} → {−1, 1}, (i.e. a coloring of {1, …, n} with two colors, say red and blue) define the discrepancy of S with respect to X to be dX(S)=|∑i∈SX(i)| (the difference between the reds and blues on S).
D. Hajela
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COMPUTING SANSKRUTI INDEX OF V-PHENYLENIC NANOTUBES AND NANOTORI
, 2017 Among topological descriptors connectivity topological indices are very important and they have a prominent role in chemistry. One of them is Sanskruti index defined as S(G) = ∑ uv∈E(G)( SuSv Su+Sv−2 ) where Su is the summation of degrees of all ...
Huiyan Jiang +4 more
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