On a conjecture of H. Gupta
نویسندگان
چکیده
Denote by r(n) the length of a shortest integer sequence on a circle containing all permutations of the set {1, 2, . . . , n} as subsequences. Hansraj Gupta conjectured in 1981 that r(n) 6 n 2 2 . In this paper, we confirm the conjecture for the case where n is even and show that r(n) < n 2 2 + n 4 − 1 if n is odd. © 2012 Elsevier B.V. All rights reserved.
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ورودعنوان ژورنال:
- Discrete Mathematics
دوره 312 شماره
صفحات -
تاریخ انتشار 2012