A graph is uniquely Hamiltonian if it contains exactly one Hamiltonian cycle. In this note, we prove that claw-free graphs with minimum degree at least 3 are not uniquely Hamiltonian. We also show that this is best possible by exhibiting uniquely Hamiltonian claw-free graphs with minimum degree 2 and arbitrary maximum degree. Finally, we show that a construction due to Entringer and Swart can be modified to construct triangle-free uniquely Hamiltonian graphs with minimum degree 3.
@article{bwmeta1.element.doi-10_7151_dmgt_1784, author = {Ben Seamone}, title = {On Uniquely Hamiltonian Claw-Free and Triangle-Free Graphs}, journal = {Discussiones Mathematicae Graph Theory}, volume = {35}, year = {2015}, pages = {207-214}, zbl = {1311.05104}, language = {en}, url = {http://dml.mathdoc.fr/item/bwmeta1.element.doi-10_7151_dmgt_1784} }
Ben Seamone. On Uniquely Hamiltonian Claw-Free and Triangle-Free Graphs. Discussiones Mathematicae Graph Theory, Tome 35 (2015) pp. 207-214. http://gdmltest.u-ga.fr/item/bwmeta1.element.doi-10_7151_dmgt_1784/
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