Abstract
Khalifeh, Yousefi-Azari, Ashrafi and Wagner [M.K. Khalifeh, H. Yousefi-Azari, A.R. Ashrafi, S.G. Wagner, Some new results on distance-based graph invariants, European J. Combin. 30 (2009) 1149-1163] conjectured that for a connected graph G on n vertices and m edges with Szeged index Sz, Sz=mn2/4 if and only if G is a regular bipartite graph. In this note, we disprove this conjecture and then prove a stronger result from which it follows that the equality holds if and only if G is a transmission-regular bipartite graph.
| Original language | English |
|---|---|
| Pages (from-to) | 1662-1666 |
| Number of pages | 5 |
| Journal | European Journal of Combinatorics |
| Volume | 31 |
| Issue number | 7 |
| DOIs | |
| Publication status | Published - Oct 2010 |
| Externally published | Yes |
ASJC Scopus subject areas
- Discrete Mathematics and Combinatorics