Let G be chosen uniformly at random from the set G G r, n of r-regular graphs w x ลฝ . with vertex set n . We describe polynomial time algorithms that whp i find a ลฝ . Hamilton cycle in G, and ii approximately count the number of Hamilton cycles in G.
Counting small cycles in generalized de Bruijn digraphs
โ Scribed by Hasunuma, Toru; Shibata, Yukio
- Publisher
- John Wiley and Sons
- Year
- 1997
- Tongue
- English
- Weight
- 143 KB
- Volume
- 29
- Category
- Article
- ISSN
- 0028-3045
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โฆ Synopsis
In this paper, we count small cycles in generalized de Bruijn digraphs. Let n ร pd h , where d ร / p, and g l ร gcd(d l 0 1, n). We show that if p รต d 3 and k ยฐ๏ฃฐlog d n๏ฃป / 1, or p รบ d 3 and k ยฐh / 3, then the number of cycles of length k in a generalized de Bruijn digraph G B (n, d) is given by 1/ k อ l รk m(k/l)g l ๏ฃฎd l / g l ๏ฃน , where m is the Mo ยจbius function and ๏ฃฎr๏ฃน denotes the smallest integer not smaller than a real number r.
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