Loop of length 22 starting with a string of length 11
found after enumerating 15638 derivations:

.ac.bcbcbcbbc
	rule ac -> b at position 0
.b.bcbcbcbbc
	rule bb -> cbcaa at position 0
.cbcaa.cbcbcbbc
	rule ac -> b at position 4
.cbcab.bcbcbbc
	rule bb -> cbcaa at position 4
.cbcacbcaa.cbcbbc
	rule ac -> b at position 3
.cbcbbcaa.cbcbbc
	rule bb -> cbcaa at position 3
.cbccbcaacaa.cbcbbc
	rule ac -> b at position 7
.cbccbcabaa.cbcbbc
	rule ac -> b at position 9
.cbccbcabab.bcbbc
	rule bb -> cbcaa at position 9
.cbccbcabacbcaa.cbbc
	rule ac -> b at position 8
.cbccbcabbbcaa.cbbc
	rule bb -> cbcaa at position 7
.cbccbcacbcaabcaa.cbbc
	rule ab ->  at position 11
.cbccbcacbcacaa.cbbc
	rule ac -> b at position 10
.cbccbcacbcbaa.cbbc
	rule ac -> b at position 12
.cbccbcacbcbab.bbc
	rule bb -> cbcaa at position 12
.cbccbcacbcbacbcaa.bc
	rule ac -> b at position 11
.cbccbcacbcbbbcaa.bc
	rule bb -> cbcaa at position 11
.cbccbcacbcbcbcaacaa.bc
	rule ac -> b at position 15
.cbccbcacbcbcbcabaa.bc
	rule ab ->  at position 17
.cbccbcacbcbcbcaba.c
	rule ac -> b at position 16
.cbccbcacbcbcbcabb.
	rule bb -> cbcaa at position 15
.cbccbcacbcbcbcacbcaa.
	rule ac -> b at position 14
.cbccbcacbcbcbcbbcaa.