Results 21 to 30 of about 4,554,566 (196)
Sharp bounds for the second Zagreb index and co-index under trees of given conditions
Mathematics OpenThe second Zagreb index and co-index are two important graph invariants. They are defined as [Formula: see text] and [Formula: see text], respectively, where [Formula: see text] is the complement of G and [Formula: see text] is the degree of a vertex u ...
Ziyang Zhao, Zunzheng Chen
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GTI-space : the space of generalized topological indices [PDF]
, 2008 A new extension of the generalized topological indices (GTI) approach is carried out torepresent 'simple' and 'composite' topological indices (TIs) in an unified way.
Matamala, Adelio R. +2 more
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On α-adjacency energy of graphs and Zagreb index [PDF]
AKCE International Journal of Graphs and Combinatorics, 2021 Let $A(G)$ be the adjacency matrix and $D(G)$ be the diagonal matrix of the vertex degrees of a simple connected graph $G$. Nikiforov defined the matrix $A_α(G)$ of the convex combinations of $D(G)$ and $A(G)$ as $A_α(G)=αD(G)+(1-α)A(G)$, for $0\leq α\leq 1$.
Shariefuddin Pirzada +3 more
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Smarandache-Zagreb Index on Three Graph Operators [PDF]
, 2010 Many researchers have studied several operators on a connected graph in which one make an attempt on subdivision of its edges. In this paper, we show how the Zagreb indices, a particular case of Smarandache-Zagreb index of a graph changes with these ...
Ranjini, P.S., Lokesha, V.
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Bounds on Szeged and PI Indexes in terms of Second Zagreb Index [PDF]
, 2012 In this short note, we studied the vertex version and the edge version of the Szeged index and the PI index and obtained bounds for these indices in terms of the Second Zagreb index.
Ranjini P.S. +2 more
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On the first Zagreb Index of Polygraphs
Electronic Notes in Discrete Mathematics, 2014 Abstract One of the most popular topological indices is the Zagreb index, introduced by Gutman and Trinajstic in 1972, which is the sum of squares of degree sequence of a (chemical) graph G. In this paper, we obtain an upper bound for the Zagreb index of polygraphs, rotagraphs and fasciagraphs.
Hossein Shabani, Reza Kahkeshani
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Bounds on the first leap Zagreb index of trees
Karpatsʹkì Matematičnì Publìkacìï, 2021 The first leap Zagreb index $LM1(G)$ of a graph $G$ is the sum of the squares of its second vertex degrees, that is, $LM_1(G)=\sum_{v\in V(G)}d_2(v/G)^2$, where $d_2(v/G)$ is the number of second neighbors of $v$ in $G$.
N. Dehgardi, H. Aram
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Topological Indices of H-Naphtalenic Nanosheet
Open Chemistry, 2018 In chemical graph theory, a single numeric number related to a chemical structure is called a topological descriptor or topological index of a graph.
Idrees Nazeran +4 more
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The unofficial economy in Croatia: causes, size and consequences [PDF]
, 1997 This Occasional Paper reports the research results of a project on the unofficial economy in Croatia conducted by the Institute of Public Finance in Zagreb for the Croatian Ministry of Finance.
Bicanic, Ivo +3 more
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