Locating Reducible Words - Free Groups

The main function locates all reducible and cyclically reducible words.

The function freegroup.m uses a sequential pattern generator (NLLSG.m) to exaust the ordered exponential powerset of combinations of 2*k elements from which the first half rerpesents group elements and the second half their inverses. Then it isolates all coincidence events between two consecutive inverse symbols and finds the number of removed pairs for each reducible pattern. Check also http://en.wikipedia.org/wiki/Free_group