6 papers
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…
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…
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…
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…
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…
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…