Abstract
For a (molecular) graph, the first and second Zagreb indices (M1 and M2) are two well-known topological indices in chemical graph theory introduced in 1972 by Gutman and Trinajstić. Let Gn,m be the set of connected graphs of order n and with m edges. In this paper we characterize the extremal graphs from Gn,m with n + 2 ≥ m ≥ 2n-4 with maximal first Zagreb index and from Gn,m with m-n = (k2)-k for k ≥ 4 with maximal second Zagreb index, respectively. Finally a related conjecture has been proposed to the extremal graphs with respect to second Zagreb index.
| Original language | English |
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| Pages (from-to) | 641-654 |
| Number of pages | 14 |
| Journal | Match |
| Volume | 72 |
| Issue number | 3 |
| State | Published - 2014 |