In this paper rooted loopless (near) 4-regular maps on surfaces such as the sphere and the projective plane are counted and exact formulae with up to three or four parameters for such maps are given. Several classical results on regular maps and one-faced maps are deduced.
Enumeration of 2 -connected Loopless 4 -regular Maps on the Plane
β Scribed by Han Ren; Yanpei Liu; Zhaoxiang Li
- Publisher
- Elsevier Science
- Year
- 2002
- Tongue
- English
- Weight
- 195 KB
- Volume
- 23
- Category
- Article
- ISSN
- 0195-6698
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β¦ Synopsis
In this paper rooted (near-) 4-regular maps on the plane are counted with respect to the root-valency, the number of edges, the number of inner faces, the number of non-root vertex loops, the number of non-root vertex blocks, and the number of multi-edges. As special cases, formulae of several types of rooted 4-regular maps such as 2-connected 4-regular planar maps, rooted 2-connected (connected) 4-regular planar maps without loops are also presented. Several known results on 4-regular maps and trees of Tutte are also concluded. Finally, asymptotic formulae for the numbers of those types of maps are given.
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