Abstract
An edgee in a 3-connected graphG is contractible if the contraction ofe inG results in a 3-connected graph; otherwisee is non-contractible. In this paper, we prove that the number of non-contractible edges in a 3-connected graph of orderp≥5 is at most
and show that this upper bound is the best possible for infinitely many values ofp.
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Partially supported by Nihon University Research Grant B90-026
Partially supported by NSF under grant No. DMS-9105173
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Egawa, Y., Ota, K., Saito, A. et al. Non-contractible edges in a 3-connected graph. Combinatorica 15, 357–364 (1995). https://doi.org/10.1007/BF01299741
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DOI: https://doi.org/10.1007/BF01299741