Counting Occurrences of a Pattern of Length Three with at most two Distinct Letters in a k-ary Word
نویسندگان
چکیده
Define τ(π) to be the number of subsequences of π that are order-isomorphic to τ . Let τ be a pattern of length three with at most two distinct letters, namely, τ ∈ {111, 112, 121, 122, 211, 212, 221}. In this paper, we give an algorithm for finding the generating function wτ ;r(n; y) = ∑
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ورودعنوان ژورنال:
- Journal of Automata, Languages and Combinatorics
دوره 21 شماره
صفحات -
تاریخ انتشار 2016