**Abstract:**

Fascinating objects can arise as variants of well-studied ones. In 2017, Brenti and Carnevale introduced an odd analogue of the classical permutation diagram. This gives rise to odd analogues of other permutation aspects, like length and inversions. These odd analogues do not behave exactly like their classical cousins and, in particular, multiple permutations can have the same odd diagram. This prompts the study of "odd diagram classes:" sets of permutations having the same odd diagram. We will discuss the rich combinatorial structure of these classes, including connections to pattern avoiding permutations and the Bruhat order.

This is joint work with Francesco Brenti and Angela Carnevale.

**Note: This talk begins with a pre-seminar (aimed at graduate students) at 3:30–4:00. The main talk starts at 4:10.**

**Join Zoom Meeting: https://washington.zoom.us/j/ 91547335974Meeting ID: 915 4733 5974**