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    Connected factors in graphs - a survey

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    2-factors in 32\frac{3}{2}-tough plane triangulations

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    In 1956, Tutte proved the celebrated theorem that every 4-connected planar graph is hamiltonian. This result implies that every more than 32\frac{3}{2}-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 32\frac{3}{2}. In fact, the graphs Owens constructed do not even contain a 2-factor. Thus the toughness of exactly 32\frac{3}{2} 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 32\frac{3}{2}-tough planar graph on at least three vertices has a 2-factor

    On some intriguing problems in Hamiltonian graph theory -- A survey

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    We survey results and open problems in Hamiltonian graph theory centred around three themes: regular graphs, tt-tough graphs, and claw-free graphs

    Stability number and f-factors in graphs

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    We present a new sufficient condition on stability number and toughness of the graph to have an f-factor
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