Loop of length 11 starting with a string of length 8
found after enumerating 19876 derivations:

.ab.bbbcbb
	rule ab -> bbaca at position 0
.bbaca.bbbcbb
	rule ab -> bbaca at position 4
.bbacbbaca.bbcbb
	rule b ->  at position 4
.bbacbaca.bbcbb
	rule a ->  at position 5
.bbacbca.bbcbb
	rule cbc ->  at position 3
.bbaa.bbcbb
	rule ab -> bbaca at position 3
.bbabbaca.bcbb
	rule a ->  at position 7
.bbabbac.bcbb
	rule cbc ->  at position 6
.bbabba.bb
	rule ab -> bbaca at position 5
.bbabbbbaca.b
	rule a ->  at position 7
.bbabbbbca.b
	rule ab -> bbaca at position 8
.bbabbbbcbbaca.