Speaker: Dr. Julian West

Title: Constrained swapping in permutations

We look at a family of problems having to do with replacing one
subpattern in a permutation by a different one. It is often interesting
to ask how many equivalence classes we obtain in this way, and even more
often interesting to ask how many permutations are in the equivalence
class of the identity permutation. We discover many well-known sequences
such as the Fibonacci numbers and Catalan numbers, and also some
less-famous sequences.