Enumerating Permutations by their Run Structure
نویسندگان
چکیده
منابع مشابه
Enumerating Permutations by their Run Structure
Motivated by a problem in quantum field theory, we study the up and down structure of circular and linear permutations. In particular, we count the length of the (alternating) runs of permutations by representing them as monomials and find that they can always be decomposed into so-called ‘atomic’ permutations introduced in this work. This decomposition allows us to enumerate the (circular) per...
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In an exercise in the first volume of his famous series of books, Knuth considered sorting permutations by passing them through a stack. Many variations of this exercise have since been considered, including allowing multiple passes through the stack and using different data structures. We are concerned with a variation using pop-stacks that was introduced byAvis andNewborn in 1981. Let Pk(x) b...
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ژورنال
عنوان ژورنال: The Electronic Journal of Combinatorics
سال: 2014
ISSN: 1077-8926
DOI: 10.37236/4235