Abstract
The connectivity index χ1(G) of a graph G is the sum of the weights d(u)d(v) of all edges uv of G, where d(u) denotes the degree of the vertex u. Let T(n, r) be the set of trees on n vertices with diameter r. In this paper, we determine all trees in T(n, r) with the largest and the second largest connectivity index. Also, the trees in T(n, r) with the largest and the second largest connectivity index are characterized.
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References
Bollobás B., Erdös P. (1998) . Ars Combin. 50: 225–233
Clark L.H., Moon J.W. (2000) . Ars Combin. 54: 223–235
Gutman I., Lepović M. (2001) . J. Serb. Chem. Soc. 66: 605–611
Gutman I., Ruscić B., Trinajstić N. (1975) . J. Chem. Phys. 62: 3399–3405
Gutman I., Trinajstić N. (1972) . Chem. Phys. Lett. 17: 535–538
Kier L.B., Hall L.H. (1976) Molecular Connectivity in Chemistry and Drug Research. Academic Press, San Francisco
L.B. Kier, L.H. Hall, Molecular Connectivity in Structure-Activity Analysis (Wiley, 1986)
Li X., Yang Y. (2004) . MATCH Commu. Math. Comput. Chem. 51: 155–166
Li X., Zhao H. (2004) . MATCH Commun. Math. Comput. Chem. 50: 57–62
Liu H., Lu M., Tian F. (2006) . Disc. Appl. Math. 154: 106–109
Lu M., Liu H., Tian F. (2004) . MATCH Commun. Math. Comput. Chem. 51: 149–154
Mihatić Z., Trinajstić N. (1992) . J. Chem. Educ. 69: 701–702
Randić M. (1975) . J. Am. Chem. Soc. 97: 6609–6615
Todeschini R., Consonni V. (2000) Handbook of Molecular Descriptors. Wiley-VCH, Weinheim
Yu P. (1998) . J. Math. Stud. 5 (Chinese) 31: 225–230
Zhao H., Li X. (2004) . MATCH Communi. Math. Comput. Chem. 51: 167–178
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Mei Lu is partially supported by NNSFC (No. 10571105).
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Jiang, Y., Lu, M. On the connectivity index of trees. J Math Chem 43, 955–965 (2008). https://doi.org/10.1007/s10910-007-9281-3
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DOI: https://doi.org/10.1007/s10910-007-9281-3