A nearly sharp lower bound on the length of the longest trail in a graph on n vertices and average degree k is given provided the graph is dense enough (k ≥ 12.5).
@article{bwmeta1.element.doi-10_2478_s11533-013-0285-x, author = {Vajk Sz\'ecsi}, title = {On the minimal length of the longest trail in a fixed edge-density graph}, journal = {Open Mathematics}, volume = {11}, year = {2013}, pages = {1831-1837}, zbl = {1277.05089}, language = {en}, url = {http://dml.mathdoc.fr/item/bwmeta1.element.doi-10_2478_s11533-013-0285-x} }
Vajk Szécsi. On the minimal length of the longest trail in a fixed edge-density graph. Open Mathematics, Tome 11 (2013) pp. 1831-1837. http://gdmltest.u-ga.fr/item/bwmeta1.element.doi-10_2478_s11533-013-0285-x/
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