Avoiding 2-letter signed patterns

T. Mansour; J. West

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arXiv · math/0207204

Avoiding 2-letter signed patterns

T. Mansour·J. West

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Abstract

Let B_n be the hyperoctahedral group; that is, the set of all signed permutations on n letters, and let B_n(T) be the set of all signed permutations in B_n which avoids a set T of signed patterns. In this paper, we find all the cardinalities of the sets B_n(T) where $T \subseteq B_2$. This allow us to express these cardinalities via inverse of binomial coefficients, binomial coefficients, Catalan numbers, and Fibonacci numbers.

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T. Mansour, J. West. 2002-07-23. Avoiding 2-letter signed patterns. https://arxiv.org/abs/math/0207204

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