The statistic ``number of udu's'' in Dyck paths
This paper studies the enumeration of Dyck paths by the number of \(udu\)'s (up-down-up). More precisely, the enumeration of Dyck paths with given semilength and given number of \(udu\)'s is obtained. An \(udu\) is said to be at low (high) level, if its peak is at level (greater than) one. Enumeration of Dyck paths with given semilength and given number of low (high) level \(udu\)'s is obtained.
scientific article; zbMATH DE number 2116272