The University of Michigan Combinatorics Seminar
Winter 2004
February 13, 4:10-5:00, 3866 East Hall

Packing density of permutations, patterns and words

Peter Hästö

U. Michigan


In this talk I will define the packing density of a permutation, a pattern or a word. The packing density measures how many times a given word can occur in a word of given (large) length. I will present results by Price, by Albert, Atkinson, Handley, Holton & Stromquist, as well as by Burstein, Mansour and myself (which, to the best of my knowledge, exhaust what is known about packing density).

The talk will be fairly elementary in nature; the techniques are basic counting and some elementary estimates.

Much of the material to be presented has appeared in the EJC, and can be downloaded at (Vol 9 No. R5, Vol 9(2) No. R1, Vol 9(2) No. R20).