Enumeration of eulerian and unicursal planar maps
نویسندگان
چکیده
Sum-free enumerative formulae are derived for several classes of rooted planar maps with no vertices of odd valency (eulerian maps) and with two vertices of odd valency (unicursal maps). As corollaries we obtain simple formulae for the numbers of unrooted eulerian and unicursal planar maps. Also, we obtain a sum-free formula for the number of rooted bi-eulerian (eulerian and bipartite) maps and some related results.
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ورودعنوان ژورنال:
- Discrete Mathematics
دوره 282 شماره
صفحات -
تاریخ انتشار 2004