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2-factors in -tough plane triangulations
In 1956, Tutte proved the celebrated theorem that every 4-connected planar
graph is hamiltonian. This result implies that every more than
-tough planar graph on at least three vertices is hamiltonian and
so has a 2-factor. Owens in 1999 constructed non-hamiltonian maximal planar
graphs of toughness arbitrarily close to . In fact, the graphs
Owens constructed do not even contain a 2-factor. Thus the toughness of exactly
is the only case left in asking the existence of 2-factors in
tough planar graphs. This question was also asked by Bauer, Broersma, and
Schmeichel in a survey. In this paper, we close this gap by showing that every
maximal -tough planar graph on at least three vertices has a
2-factor
On some intriguing problems in Hamiltonian graph theory -- A survey
We survey results and open problems in Hamiltonian graph theory centred around three themes: regular graphs, -tough graphs, and claw-free graphs
Stability number and f-factors in graphs
We present a new sufficient condition on stability number and toughness of
the graph to have an f-factor
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