Cheyne Homberger

Pattern Avoiding Involutions: Exact and Asymptotic Enumeration

with Miklós Bóna, Jay Pantone, Vince Vatter


We consider the enumeration of pattern-avoiding involutions, focusing in particular on sets defined by avoiding a single pattern of length 4. As we demonstrate, the numerical data for these problems demonstrates some surprising behavior. This strange behavior even provides some very unexpected data related to the number of 1324-avoiding permutations.