Loop of length 18 starting with a string of length 9
found after enumerating 2560 derivations:

.cbb.bbbbbb
	rule cbb -> abacc at position 0
.abacc.bbbbbb
	rule cbb -> abacc at position 4
.abacabacc.bbbb
	rule ab -> bb at position 4
.abacbbacc.bbbb
	rule cbb -> abacc at position 8
.abacbbacabacc.bb
	rule ab -> bb at position 8
.abacbbacbbacc.bb
	rule cbb -> abacc at position 7
.abacbbaabaccacc.bb
	rule ab -> bb at position 7
.abacbbabbaccacc.bb
	rule ab -> bb at position 6
.abacbbbbbaccacc.bb
	rule cbb -> abacc at position 14
.abacbbbbbaccacabacc.
	rule ab -> bb at position 14
.abacbbbbbaccacbbacc.
	rule cbb -> abacc at position 13
.abacbbbbbaccaabaccacc.
	rule ab -> bb at position 13
.abacbbbbbaccabbaccacc.
	rule ab -> bb at position 12
.abacbbbbbaccbbbaccacc.
	rule cbb -> abacc at position 11
.abacbbbbbacabaccbaccacc.
	rule ab -> bb at position 11
.abacbbbbbacbbaccbaccacc.
	rule cbb -> abacc at position 10
.abacbbbbbaabaccaccbaccacc.
	rule ab -> bb at position 10
.abacbbbbbabbaccaccbaccacc.
	rule ab -> bb at position 9
.abacbbbbbbbbaccaccbaccacc.