J. Integer Seq. 20(1), Article 17.1.5, 13 p. (2017)
Summary
Summary: Based on Touchard's identity, we give a simple derivation for the enumeration of the N/S/E/W walks that remain on the north side of the origin.
Mathematics Subject Classification
05A15
Keywords/Phrases
path enumerations, drunken walk, random walk, Dyck path, lattice path, touchard's identity, Catalan number, Motzkin number, central binomial factor
