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On certain Hamiltonian cycles in planar graphs

✍ Scribed by B�hme, T.; Harant, J.; Tk�?, M.


Publisher
John Wiley and Sons
Year
1999
Tongue
English
Weight
162 KB
Volume
32
Category
Article
ISSN
0364-9024

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✦ Synopsis


The problem is considered under which conditions a 4-connected planar or projective planar graph has a Hamiltonian cycle containing certain prescribed edges and missing certain forbidden edges. The results are applied to obtain novel lower bounds on the number of distinct Hamiltonian cycles that must be present in a 5-connected graph that is embedded into the plane or into the projective plane with face-width at least five. Especially, we show that every 5-connected plane or projective plane triangulation on n vertices with no non-contractible cyles of length less than five contains at least 2 O(n 1/4 ) distinct Hamiltonian cycles.


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