Circular Digraph Walks, k-Balanced Strings, Lattice Paths and Chebychev Polynomials
نویسندگان
چکیده
We count the number of walks of length n on a k-node circular digraph that cover all k nodes in two ways. The first way illustrates the transfer-matrix method. The second involves counting various classes of height-restricted lattice paths. We observe that the results also count so-called k-balanced strings of length n, generalizing a 1996 Putnam problem. Corresponding Author This work was supported by the 973 Project, the PCSIRT Project of the Ministry of Education, the Ministry of Science and Technology, and the National Science Foundation of China. the electronic journal of combinatorics 15 (2008), #R00 1
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ورودعنوان ژورنال:
- Electr. J. Comb.
دوره 15 شماره
صفحات -
تاریخ انتشار 2008