A New Class of Wilf-Equivalent Permutations
نویسنده
چکیده
For about 10 years, the classification up to Wilf equivalence of permutation patterns was thought completed up to length 6. In this paper, we establish a new class of Wilf-equivalent permutation patterns, namely, (n −1, n −2, n, τ ) ∼ (n −2, n, n −1, τ ) for any τ ∈ Sn−3. In particular, at level n = 6, this result includes the only missing equivalence (546213) ∼ (465213), and for n = 7 it completes the classification of permutation patterns by settling all remaining cases in S7.
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تاریخ انتشار 2002