TY - JOUR A2 - Jaballah, Ali AU - Nacaroglu, Yasar PY - 2021 DA - 2021/05/07 TI - The Sigma Coindex of Graph Operations SP - 5534444 VL - 2021 AB - The sigma coindex is defined as the sum of the squares of the differences between the degrees of all nonadjacent vertex pairs. In this paper, we propose some mathematical properties of the sigma coindex. Later, we present precise results for the sigma coindices of various graph operations such as tensor product, Cartesian product, lexicographic product, disjunction, strong product, union, join, and corona product. SN - 2314-4629 UR - https://doi.org/10.1155/2021/5534444 DO - 10.1155/2021/5534444 JF - Journal of Mathematics PB - Hindawi KW - ER -