A Linear Upper Bound in Extremal Theory of Sequences
نویسنده
چکیده
An extremal problem considering sequences related to Davenport-Schinzel sequences is investigated in this paper. We prove that f(x1x i 2..x i kx i 1x i 2..x i k, n) = O(n) where the quantity on the left side is defined as the maximum length m of the sequence u = a1a2..am of integers such that 1) 1 ≤ ar ≤ n, 2) ar = as, r 6= s implies |r− s| ≥ k and 3) u contains no subsequence of the type x1...xkx1...xk (x stands for xx..x i-times).
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عنوان ژورنال:
- J. Comb. Theory, Ser. A
دوره 68 شماره
صفحات -
تاریخ انتشار 1994