YES Problem: b(a(b(b(x)))) -> b(b(b(a(b(x))))) b(a(a(b(b(x))))) -> b(a(b(b(a(a(b(x))))))) b(a(a(a(b(b(x)))))) -> b(a(a(b(b(a(a(a(b(x))))))))) Proof: Church Rosser Transformation Processor (no redundant rules): strict: b(a(a(a(b(b(x)))))) -> b(a(a(b(b(a(a(a(b(x))))))))) b(a(a(b(b(x))))) -> b(a(b(b(a(a(b(x))))))) b(a(b(b(x)))) -> b(b(b(a(b(x))))) weak: critical peaks: 9 b(a(a(a(b(b(a(a(b(b(a(a(a(b(x46)))))))))))))) <-0|0,0,0,0,0[]- b(a ( a(a(b(b(a(a(a(b(b(x46))))))))))) -0| []-> b(a ( a ( b ( b ( a(a(a(b(a(a(a(b(b(x46)))))))))))))) b(a(a(b(b(a(a(b(b(a(a(a(b(x47))))))))))))) <-0|0,0,0,0[]- b(a(a(b(b(a(a(a(b(b(x47)))))))))) -1| []-> b(a ( b ( b(a(a(b(a(a(a(b(b(x47)))))))))))) b(a(b(b(a(a(b(b(a(a(a(b(x48)))))))))))) <-0|0,0,0[]- b(a(b(b(a(a(a(b(b(x48))))))))) -2| []-> b(b(b(a(b(a(a(a(b(b(x48)))))))))) b(a(a(a(b(b(a(b(b(a(a(b(x49)))))))))))) <-1|0,0,0,0,0[]- b(a(a(a(b(b(a(a(b(b(x49)))))))))) -0| []-> b(a( a ( b ( b(a(a(a(b(a(a(b(b(x49))))))))))))) b(a(a(b(b(a(b(b(a(a(b(x50))))))))))) <-1|0,0,0,0[]- b(a(a(b(b(a(a(b(b(x50))))))))) -1| []-> b(a(b(b(a(a(b(a(a(b(b(x50))))))))))) b(a(b(b(a(b(b(a(a(b(x51)))))))))) <-1|0,0,0[]- b(a(b(b(a(a(b(b(x51)))))))) -2| []-> b(b(b(a(b(a(a(b(b(x51))))))))) b(a(a(a(b(b(b(b(a(b(x52)))))))))) <-2|0,0,0,0,0[]- b(a(a(a(b(b(a(b(b(x52))))))))) -0| []-> b(a(a(b(b(a(a(a(b(a(b(b(x52)))))))))))) b(a(a(b(b(b(b(a(b(x53))))))))) <-2|0,0,0,0[]- b(a(a(b(b(a(b(b(x53)))))))) -1| []-> b(a(b(b(a(a(b(a(b(b(x53)))))))))) b(a(b(b(b(b(a(b(x54)))))))) <-2|0,0,0[]- b(a(b(b(a(b(b(x54))))))) -2| []-> b(b(b(a(b(a(b(b(x54)))))))) Closedness Processor (*strongly -- <=7 steps*): Qed