Abstract
A map is 4-regular unicursal if all its vertices are 4-valent except two odd-valent vertices. This paper investigates the number of rooted 4-regular unicursal planar maps and presents some formulae for such maps with four parameters: the number of edges, the number of inner faces and the valencies of the two odd vertices.
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The authors are grateful to the referees for their careful reading of this paper. Their constructive suggestions enabled us to make some major revisions which made the paper more readable and concrete.
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Supported by the National Natural Science Foundation of China (No. 10271017,11371133,11571044), the Natural Science Foundation Project of Chongqing (No. cstc2012jjA00041,cstc2014jcyjA00041) and the Innovation Foundation of Chongqing (No. KJTD201321).
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Long, Sd., Cai, Jl. Counting rooted 4-regular unicursal planar maps. Acta Math. Appl. Sin. Engl. Ser. 33, 909–918 (2017). https://doi.org/10.1007/s10255-017-0706-x
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DOI: https://doi.org/10.1007/s10255-017-0706-x