Certification Problem

Input (TPDB SRS_Standard/Waldmann_07_size12/size-12-alpha-3-num-450)

The rewrite relation of the following TRS is considered.

a(x1) b(c(x1)) (1)
a(b(b(x1))) c(a(a(a(x1)))) (2)
c(c(x1)) x1 (3)

Property / Task

Prove or disprove termination.

Answer / Result

No.

Proof (by matchbox @ termCOMP 2023)

1 Loop

The following loop proves nontermination.

t0 = c(b(c(b(b(a(a(a(a(c(a(a(b(x1)))))))))))))
c(b(c(b(b(a(a(a(b(c(c(a(a(b(x1))))))))))))))
c(b(c(b(b(a(a(a(b(a(a(b(x1))))))))))))
c(b(c(b(b(a(a(a(b(b(c(a(b(x1)))))))))))))
c(b(c(b(b(a(a(c(a(a(a(c(a(b(x1))))))))))))))
c(b(c(b(b(a(a(c(a(a(b(c(c(a(b(x1)))))))))))))))
c(b(c(b(b(a(a(c(a(a(b(a(b(x1)))))))))))))
c(b(c(b(b(a(b(c(c(a(a(b(a(b(x1))))))))))))))
c(b(c(b(b(a(b(a(a(b(a(b(x1))))))))))))
c(b(c(b(b(a(b(a(a(b(b(c(b(x1)))))))))))))
c(b(c(b(b(a(b(a(c(a(a(a(c(b(x1))))))))))))))
c(b(c(b(b(a(b(a(c(a(a(b(c(c(b(x1)))))))))))))))
c(b(c(b(b(a(b(a(c(a(a(b(b(x1)))))))))))))
c(b(c(b(b(a(b(b(c(c(a(a(b(b(x1))))))))))))))
c(b(c(b(b(a(b(b(a(a(b(b(x1))))))))))))
c(b(c(b(b(a(b(b(b(c(a(b(b(x1)))))))))))))
c(b(c(b(b(a(b(b(b(c(c(a(a(a(x1))))))))))))))
c(b(c(b(b(a(b(b(b(a(a(a(x1))))))))))))
c(b(c(b(b(a(b(b(b(b(c(a(a(x1)))))))))))))
c(b(c(b(b(c(a(a(a(b(b(c(a(a(x1))))))))))))))
c(b(c(b(b(c(a(a(c(a(a(a(c(a(a(x1)))))))))))))))
c(b(c(b(b(c(a(b(c(c(a(a(a(c(a(a(x1))))))))))))))))
c(b(c(b(b(c(a(b(a(a(a(c(a(a(x1))))))))))))))
c(b(c(b(b(c(a(b(a(a(b(c(c(a(a(x1)))))))))))))))
c(b(c(b(b(c(a(b(a(a(b(a(a(x1)))))))))))))
c(b(c(b(b(c(a(b(b(c(a(b(a(a(x1))))))))))))))
c(b(c(b(b(c(c(a(a(a(c(a(b(a(a(x1)))))))))))))))
c(b(c(b(b(a(a(a(c(a(b(a(a(x1)))))))))))))
c(b(c(b(b(a(a(a(c(a(b(b(c(a(x1))))))))))))))
c(b(c(b(b(a(a(a(c(c(a(a(a(c(a(x1)))))))))))))))
c(b(c(b(b(a(a(a(a(a(a(c(a(x1)))))))))))))
c(b(c(b(b(a(a(a(a(a(b(c(c(a(x1))))))))))))))
c(b(c(b(b(a(a(a(a(a(b(a(x1))))))))))))
c(b(c(b(b(a(a(a(a(a(b(b(c(x1)))))))))))))
c(b(c(b(b(a(a(a(a(c(a(a(a(c(x1))))))))))))))
c(b(c(b(b(a(a(a(a(c(a(a(b(c(c(x1)))))))))))))))
= t35
where t35 = t0σ and σ = {x1/c(c(x1))}