Abstract
Jaeger et al. conjectured that every 5-edge-connected graph is \(Z_3\)-connected, which is equivalent to that every 5-edge-connected claw-free graph is \(Z_3\)-connected by Lai et al. (Inf Process Lett 111:1085–1088, 2011), and Ma and Li (Discret Math 336:57–68, 2014). Let G be a claw-free graph on at least 3 vertices such that there are at least two common neighbors of every pair of 2-distant vertices. In this paper, we prove that G is not \(Z_3\)-connected if and only if G is one of seven specified graphs, or three families of well characterized graphs. As a corollary, G does not admit a nowhere-zero 3-flow if and only if G is one of three specified graphs or a family of well characterized graphs.



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References
Bondy, J.A., Murty, U.S.R.: Graph Theory. Springer, Berlin (2008)
Chen, J., Eschen, E., Lai, H.-J.: Group connectivity of certain graphs. Ars Comb. 89, 141–158 (2008)
Devos, M., Xu, R., Yu, G.: Nowhere-zero \(Z_3\)-flows through \(Z_3\)-connectivity. Discret. Math. 306, 26–30 (2006)
Fan, G., Zhou, C.: Ore condition and nowhere-zero 3-flows. SIAM J. Discret. Math. 22, 288–294 (2008)
Fan, G., Lai, H.-J., Xu, R., Zhang, C.-Q., Zhou, C.: Nowhere-zero 3-flows in triangularly connected graphs. J. Combin. Theory Ser. B 98, 1325–1336 (2008)
Jaeger, F., Linial, N., Payan, C., Tarsi, N.: Group connectivity of graphs—a nonhomogeneous analogue of nowhere zero flow properties. J. Combin. Theory Ser. B 56, 165–182 (1992)
Kochol, M.: An equivalent version of the 3-flow conjecture. J. Combin. Theory Ser. B 83, 258–261 (2001)
Lai, H.-J.: Group connectivity of 3-edge-connected chordal graphs. Graphs Combin. 16, 165–176 (2000)
Lai, H.-J.: Nowhere-zero 3-flows in locally connected graphs. J. Graph Theory 42, 211–219 (2003)
Lai, H.-J., Li, H., Li, P., Liang, Y., Yao, S.: Mod (2p+1)-orientations in line graphs. Inf. Process. Lett. 111, 1085–1088 (2011)
Lai, H.-J., Li, X., Shao, Y., Zhan, M.: Group connectivity and group colorings of graphs—a survey. Acta Math. Sin. (Engl. Ser.) 27, 405–434 (2011)
Li, X., Shao, Y., Lai, H.-J.: Degree condition and \(Z_3\)-connectivity. Discret. Math. 312, 1658–1669 (2012)
Lovász, L.M., Thomassen, C., Wu, Y., Zhang, C.-Q.: Nowhere-zero 3-flows and modulo \(k\)-orientations. J. Combin. Theory Ser. B 103, 587–598 (2013)
Luo, R., Xu, R., Yin, J., Yu, G.: Ore-condition and \(Z_3\)-connectivity. Eur. J. Combin. 29, 1587–1595 (2008)
Ma, J., Li, X.: Nowhere-zero \(3\)-flows of claw-free graphs. Discret. Math. 336, 57–68 (2014)
Shi, R.: 2-neighborhoods and Hamiltonian conditions. J. Graph Theory 16, 267–271 (1992)
Thomassen, C.: The weak 3-flow conjecture and the weak circular flow conjecture. J. Combin. Theory Ser. B 102, 521–529 (2012)
Tutte, W.T.: On the imbedding of linear graphs in surfaces. Proc. Lond. Math. Soc. Ser. 2(51), 474–483 (1949)
Tutte, W.T.: A contribution to the theory of chromatic polynomials. Can. J. Math. 6, 80–91 (1954)
Yang, F., Li, X.: Degree sum condition for 3-independent set and \(Z_3\)-connectivity. Discret. Math. 313, 2493–2505 (2013)
Zhang, X., Zhan, M., Xu, R., Shao, Y., Li, X., Lai, H.-J.: Degree Sum condition for \(Z_3\)-connectivity in graphs. Discret. Math. 310, 3390–3397 (2010)
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X. Li was supported by the Natural Science Foundation of China (11571134) and by Doctoral Fund of Ministry of Education of China (20130144110001).
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Huang, Z., Li, X. & Ma, J. \(Z_3\)-Connectivity of Claw-Free Graphs. Graphs and Combinatorics 33, 123–140 (2017). https://doi.org/10.1007/s00373-016-1754-3
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DOI: https://doi.org/10.1007/s00373-016-1754-3