  Suppose $n$ different pairs of socks are put in a tumble dryer. When the
dryer is finished socks are taken out one by one, if a sock matches one of the
socks on the sorting table both are removed, otherwise it is put on the table
until its partner emerges from the dryer. We note the number of socks on the
table after each of the $2n$ socks is taken from the dryer and give an explicit
formula for the probability that this sequence equals a given sequence of
length $2n$.
