Loop of length 18 starting with a string of length 10
found after enumerating 141495 derivations:

.ac.bccccbcc
	rule ac -> ccaba at position 0
.ccaba.bccccbcc
	rule a ->  at position 4
.ccab.bccccbcc
	rule bbc -> a at position 3
.ccaa.cccbcc
	rule ac -> ccaba at position 3
.ccaccaba.ccbcc
	rule ac -> ccaba at position 2
.ccccabacaba.ccbcc
	rule ac -> ccaba at position 6
.ccccabccabaaba.ccbcc
	rule a ->  at position 10
.ccccabccababa.ccbcc
	rule a ->  at position 10
.ccccabccabba.ccbcc
	rule ac -> ccaba at position 11
.ccccabccabbccaba.cbcc
	rule bbc -> a at position 9
.ccccabccaacaba.cbcc
	rule a ->  at position 11
.ccccabccaacba.cbcc
	rule ac -> ccaba at position 12
.ccccabccaacbccaba.bcc
	rule a ->  at position 16
.ccccabccaacbccab.bcc
	rule bbc -> a at position 15
.ccccabccaacbccaa.c
	rule ac -> ccaba at position 15
.ccccabccaacbccaccaba.
	rule ac -> ccaba at position 14
.ccccabccaacbccccabacaba.
	rule a ->  at position 16
.ccccabccaacbccccbacaba.
	rule ac -> ccaba at position 17
.ccccabccaacbccccbccabaaba.