Extremal Properties of the Zagreb Eccentricity Indices

We give sharp lower bounds for the Zagreb eccentricity indices of connected graphs with fixed numbers of vertices and edges, sharp lower and upper bounds for the Zagreb eccentricity indices of trees with fixed number of pendant vertices, sharp upper bounds for the Zagreb eccentricity indices of trees with fixed matching number (fixed maximum degree, respectively), and characterize the extremal graphs. (doi: 10.5562/cca2020