NO Problem: a(a(b(x1))) -> b(c(b(a(a(a(x1)))))) a(c(x1)) -> b(x1) Proof: String Reversal Processor: b(a(a(x1))) -> a(a(a(b(c(b(x1)))))) c(a(x1)) -> b(x1) Unfolding Processor: loop length: 12 terms: b(a(a(a(a(a(a(x78575))))))) a(a(a(b(c(b(a(a(a(a(x78575)))))))))) a(a(a(b(c(a(a(a(b(c(b(a(a(x78575))))))))))))) a(a(a(b(b(a(a(b(c(b(a(a(x78575)))))))))))) a(a(a(b(a(a(a(b(c(b(b(c(b(a(a(x78575))))))))))))))) a(a(a(b(a(a(a(b(c(b(b(c(a(a(a(b(c(b(x78575)))))))))))))))))) a(a(a(b(a(a(a(b(c(b(b(b(a(a(b(c(b(x78575))))))))))))))))) a(a(a(b(a(a(a(b(c(b(b(a(a(a(b(c(b(b(c(b(x78575)))))))))))))))))))) a(a(a(b(a(a(a(b(c(b(a(a(a(b(c(b(a(b(c(b(b(c(b(x78575))))))))))))))))))))))) a(a(a(b(a(a(a(b(c(a(a(a(b(c(b(a(b(c(b(a(b(c(b(b(c(b(x78575)))))))))))))))))))))))))) a(a(a(b(a(a(a(b(b(a(a(b(c(b(a(b(c(b(a(b(c(b(b(c(b(x78575))))))))))))))))))))))))) a(a(a(b(a(a(a(b(a(a(a(b(c(b(b(c(b(a(b(c(b(a(b(c(b(b(c(b(x78575)))))))))))))))))))))))))))) context: a(a(a([]))) substitution: x78575 -> b(c(b(a(b(c(b(b(c(b(a(b(c(b(a(b(c(b(b(c(b(x78575))))))))))))))))))))) Qed