Counting Stabilized-Interval-Free Permutations
نویسنده
چکیده
A stabilized-interval-free (SIF) permutation on [n] = {1, 2, ..., n} is one that does not stabilize any proper subinterval of [n]. By presenting a decomposition of an arbitrary permutation into a list of SIF permutations, we show that the generating function A(x) for SIF permutations satisfies the defining property: [xn−1]A(x)n = n! . We also give an efficient recurrence for counting SIF permutations.
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تاریخ انتشار 2004