TY  - JOUR
T1  - THE SIGMA INDEX OF GRAPH OPERATIONS
AU  - Jahanbanı, Akbar
AU  - Ediz, Süleyman
PY  - 2019
DA  - March
JF  - Sigma Journal of Engineering and Natural Sciences
JO  - SIGMA
PB  - Yildiz Technical University
WT  - DergiPark
SN  - 1304-7191
SP  - 155
EP  - 162
VL  - 37
IS  - 1
LA  - en
AB  - Let G be a graph of order n with vertices labeled as v1, v2, …,  vn. Let di be the degree of the vertex vi, for i = 1, 2, …, n. The sigma index, which have been defined very recently, of G is (G) = ΣvivjE(G)(di  dj)2. In this paper, the sigma index of the Cartesian product, composition, join and disjunction of graphs are computed. We apply some of our results to compute the sigma index of some special graph classes.
KW  - Graph operations
KW  - sigma index
KW  - zagreb index.
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UR  - https://dergipark.org.tr/en/pub/sigma/issue//1011114
L1  - https://dergipark.org.tr/en/download/article-file/2032023
ER  -