Abstract
A graph \(G\) is \(F\)-saturated if it has no \(F\) as a subgraph, but does contain \(F\) after the addition of any new edge. The saturation number, \(sat(n,F)\), is the minimum number of edges of a graph in the set of all \(F\)-saturated graphs with order \(n\). In this paper, we determine the saturation number \(sat(n,P_5\cup tP_2)\) for \(n\ge 3t+8\) and characterize the extremal graphs for \(n>(18t+76)/5\).
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References
Berge, C.: Sur le couplage maximum d’un graphe. C. R. Acad. Sci. Paris 247, 258–259 (1958)
Bohman, T., Fonoberova, M., Pikhurko, O.: The saturation function of complete partite graphs. J. Comb. 1, 149–170 (2010)
Bollobás, B.: On a conjecture of Erdős, Hajnal and Moon. Am. Math. Mon. 74, 178–179 (1967)
Bondy, J.A., Murty, U.S.R.: Graph Theory with Applicaitons. American Elsevier, New York (1976)
Bushaw, N., Kettle, N.: Turán of multiple of paths and equibipartite forests. Comb. Probab. Comput. 20, 837–853 (2011)
Chen, G., Faudree, R.J., Gould, R.J.: Saturation numbers of books. Electron. J. Comb. 15(1), 118–129 (2008)
Chen, G., Faudree J.R., Faudree R.J., Ronald J. Gould, R.J., Jacobson, M.S., Magnant, C.: Saturation number for linear forests (manuscript)
Chen, Y.: Minimum \(C_5\)-saturated graphs. J. Graph Theory 61(2), 111–126 (2009)
Chen, Y.: All minimum \(C_5\)-saturated graphs. J. Graph Theory 67(1), 9–26 (2011)
Erdős, P., Hajnal, A., Moon, J.W.: A problem in graph theory. Am. Math. Mon. 71, 1107–1110 (1964)
Faudree, J.R., Faudree, R.J., Gould, R.J., Jacobson, M.S.: Saturation numbers for trees. Electron. J. Comb. 16(1), 91–109 (2009)
Faudree, J.R., Faudree, R.J., Schmitt, J. R.: A survey of minimum saturation graphs. Electron. J. Comb. 18, #DS19 (2011)
Faudree, J.R., Ferrara, M., Gould, R.J., Jacobson, M.S.: \(tK_p\)-saturated graphs of minimum size. Discret. Math. 309(19), 5870–5876 (2009)
Faudree, R.J., Gould, R.J.: Saturation numbers for nearly complete graphs. Graphs Comb. 29, 429–448 (2013)
Kászonyi, L., Tuza, Z.: Saturated graphs with minimal number of edges. J. Graph Theory 10, 203–210 (1986)
Ollmann, L.T.: \(K_{2,2}\)-saturated graphs with a minimal number of edges. In: Proceedings of the Third Southeastern Conference on Combinatorics, Graph Theory, and Computing, pp. 367–392. Florida Atlantic Univ., Boca Raton, Fla. (1972)
Turán, P.: Eine Extremalaufgabe aus der Graphentheorie. Mat. Fiz. Lapok 48, 436–452 (1941)
Tuza, Z.: \(C_4\)-saturated graphs of minimum size. Acta Univ. Carolin. Math. Phys. 30(2), 161–167. 17th Winter School on Abstract Analysis (Srní, 1989)
Zhang, M., Luo, S., Shigeno, M.: On the number of edges in a minimum \(C_6\)-saturated graph. Graphs Comb. doi:10.1007/s00373-014-1422-4
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The authors would like to thank the referees for their helpful comments and suggestions leading to an improvement of our paper.
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Supported by the National Natural Science Foundation of China under Grants 11171129, 11271149, and 11371162, and by the Self-determined Research Funds of CCNU from the colleges basic research and operation of MOE.
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Fan, Q., Wang, C. Saturation Numbers for Linear Forests\(P_5 \cup tP_2\) . Graphs and Combinatorics 31, 2193–2200 (2015). https://doi.org/10.1007/s00373-014-1514-1
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DOI: https://doi.org/10.1007/s00373-014-1514-1