8.68/2.45 NO 8.68/2.45 8.68/2.45 8.68/2.45 The system was reversed. 8.68/2.45 8.68/2.45 Remains to prove termination of the 4-rule system 8.68/2.45 { a -> , 8.68/2.45 b a a -> c c c , 8.68/2.45 c -> a b , 8.68/2.45 b c -> } 8.68/2.45 8.68/2.45 8.68/2.45 Loop of length 16 starting with a string of length 5 using right expansion 8.68/2.45 and the encoding {a=a, b=b, c=c}: 8.68/2.45 8.68/2.45 .baa.aa 8.68/2.45 rule baa -> ccc at position 0 8.68/2.45 .ccc.aa 8.68/2.45 rule c -> ab at position 0 8.68/2.45 .abcc.aa 8.68/2.45 rule c -> ab at position 2 8.68/2.45 .ababc.aa 8.68/2.45 rule c -> ab at position 4 8.68/2.45 .ababab.aa 8.68/2.45 rule baa -> ccc at position 5 8.68/2.45 .ababaccc. 8.68/2.45 rule c -> ab at position 5 8.68/2.45 .ababaabcc. 8.68/2.45 rule baa -> ccc at position 3 8.68/2.45 .abacccbcc. 8.68/2.45 rule c -> ab at position 3 8.68/2.45 .abaabccbcc. 8.68/2.45 rule c -> ab at position 5 8.68/2.45 .abaababcbcc. 8.68/2.45 rule bc -> at position 6 8.68/2.45 .abaababcc. 8.68/2.45 rule bc -> at position 6 8.68/2.45 .abaabac. 8.68/2.45 rule c -> ab at position 6 8.68/2.45 .abaabaab. 8.68/2.45 rule baa -> ccc at position 4 8.68/2.45 .abaacccb. 8.68/2.45 rule c -> ab at position 4 8.68/2.45 .abaaabccb. 8.68/2.45 rule bc -> at position 5 8.68/2.45 .abaaacb. 8.68/2.45 rule c -> ab at position 5 8.68/2.45 .abaaaabb. 8.90/2.50 EOF