12 citations · 98 across the 59 of their papers we have counts for
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On the genus of a quotient of a numerical semigroup
Ayomikun Adeniran, Steve Butler, Colin Defant +6
We find a relation between the genus of a quotient of a numerical semigroup and the genus of itself. We use this identity to compute the genus of a quotient of when …
Stack-sorting for Words
Colin Defant, Noah Kravitz
We introduce operators and , which act on words as natural generalizations of West's stack-sorting map. We show that the heuristically slower alg…
Fertility Numbers
Colin Defant
A nonnegative integer is called a fertility number if it is equal to the number of preimages of a permutation under West's stack-sorting map. We prove structural results concerning…
Stack-Sorting Preimages of Permutation Classes
Colin Defant
We extend and generalize many of the enumerative results concerning West's stack-sorting map . First, we prove a useful theorem that allows one to efficiently compute $|s^{-1}(π…
Stack-Sorting, Set Partitions, and Lassalle's Sequence
Colin Defant, Michael Engen, Jordan A. Miller
We exhibit a bijection between recently-introduced combinatorial objects known as valid hook configurations and certain weighted set partitions. When restricting our attention to s…