collaborators

6 papers

math.CO2025

Combinatorial proofs of totals of some statistics on Catalan words

Mark Shattuck

A Catalan word is one on the alphabet of positive integers starting with in which each subsequent letter is at most one more than its predecessor. Let denote th…

math.CO2025

On ascent sequences avoiding 021 and a pattern of length four

Toufik Mansour, Mark Shattuck

Ascent sequences of length avoiding the pattern are enumerated by the -th Catalan number . In this paper, we extend this result and enu…

math.CO2025

Avoidance of vincular patterns by flattened derangements

Toufik Mansour, Mark Shattuck

In this paper, we consider the problem of avoiding a single vincular pattern of length three by derangements in the flattened sense and find explicit formulas for the generating fu…

math.CO2025

Counting k-ary words by number of adjacency differences of a prescribed size

Sela Fried, Toufik Mansour, Mark Shattuck

Recently, the general problem of enumerating permutations such that for all , where and are fixed, was consider…

math.CO2025

Enumeration of consecutive patterns in flattened Catalan words

Mark Shattuck

A Catalan word is said to be flattened if the subsequence of obtained by taking the first letter of each weakly increasing run is nondecreasing. Let denote…

math.CO2025

Further Results for the Capacity Statistic Distribution on Compositions of 1's and 2's

Mark Shattuck

In this paper, we study additional aspects of the capacity distribution on the set of compositions of consisting of 's and 's. Among our results are furth…