For a graph G, the second Zagreb eccentricity index E2(G) and eccentric connectivity index ∈c (G) are two eccentricity-based
invariants of graph G. In this paper we prove some results on the comparison between 2E (G)
m and c (G)
ξ of connected graphs G of order
n and with m edges.
The authors demonstrated how a combination of both techniques and human interventions enhances control, decision-making
and data analysis systems.
Keywords: Graph; Eccentricity (of vertex); Second Zagreb eccentricity index; Eccentric connectivity index