2 papers
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…