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A permutation is said to be \emph{alternating} if it starts with rise and then descents and rises come in turn. In this paper we study the generating function for the number of alternating permutations on letters that avoid or contain exactly once 132 and also avoid or contain exactly once an arbitrary pattern on letters. In several interesting cases the generating function depends only on and is expressed via Chebyshev polynomials of the second kind.

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