0 Permutations avoiding a pattern from S k and at least two patterns from S 3

نویسنده

  • Toufik Mansour
چکیده

In this paper, we find explicit formulas or generating functions for the cardinalities of the sets Sn(T, τ ) of all permutations in Sn that avoid a pattern τ ∈ Sk and a set T , |T | ≥ 2, of patterns from S3. The main body of the paper is divided into three sections corresponding to the cases |T | = 2, 3 and |T | ≥ 4. As an example, in the fifth section, we obtain the complete classification of all cardinalities of the sets Sn(T, τ ) for k = 4.

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Permutations avoiding a pattern from Sk and at least two patterns from S3

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تاریخ انتشار 2000