The family of 5-valent polyhedral graphs whose faces are all triangles or 3s-gons, s ≥ 9, is shown to contain non-hamiltonian graphs and to have a shortness exponent smaller than one.
Technical University Ilmenau, Institite of Mathematies, PF 327, D-98684 Ilmenau, Germany
Bibliografia
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[15] H. Walther, A non-hamiltonian five-regular multitriangular polyhedral graph (to appear).