NO Problem: a(a(b(x1))) -> a(b(c(a(a(x1))))) a(c(x1)) -> b(a(x1)) Proof: String Reversal Processor: b(a(a(x1))) -> a(a(c(b(a(x1))))) c(a(x1)) -> a(b(x1)) Unfolding Processor: loop length: 16 terms: b(a(a(a(a(a(a(x352677))))))) a(a(c(b(a(a(a(a(a(x352677))))))))) a(a(c(a(a(c(b(a(a(a(a(x352677))))))))))) a(a(a(b(a(c(b(a(a(a(a(x352677))))))))))) a(a(a(b(a(c(a(a(c(b(a(a(a(x352677))))))))))))) a(a(a(b(a(a(b(a(c(b(a(a(a(x352677))))))))))))) a(a(a(b(a(a(b(a(c(a(a(c(b(a(a(x352677))))))))))))))) a(a(a(b(a(a(b(a(a(b(a(c(b(a(a(x352677))))))))))))))) a(a(a(b(a(a(a(a(c(b(a(b(a(c(b(a(a(x352677))))))))))))))))) a(a(a(b(a(a(a(a(c(b(a(b(a(c(a(a(c(b(a(x352677))))))))))))))))))) a(a(a(b(a(a(a(a(c(b(a(b(a(a(b(a(c(b(a(x352677))))))))))))))))))) a(a(a(b(a(a(a(a(c(b(a(a(a(c(b(a(b(a(c(b(a(x352677))))))))))))))))))))) a(a(a(b(a(a(a(a(c(a(a(c(b(a(a(c(b(a(b(a(c(b(a(x352677))))))))))))))))))))))) a(a(a(b(a(a(a(a(a(b(a(c(b(a(a(c(b(a(b(a(c(b(a(x352677))))))))))))))))))))))) a(a(a(b(a(a(a(a(a(b(a(c(a(a(c(b(a(c(b(a(b(a(c(b(a(x352677))))))))))))))))))))))))) a(a(a(b(a(a(a(a(a(b(a(a(b(a(c(b(a(c(b(a(b(a(c(b(a(x352677))))))))))))))))))))))))) context: a(a(a([]))) substitution: x352677 -> a(c(b(a(b(a(c(b(a(c(b(a(b(a(c(b(a(x352677))))))))))))))))) Qed