Certification Problem

Input (TPDB SRS_Standard/Zantema_04/z046)

The rewrite relation of the following TRS is considered.

c(a(a(b(a(x1)))))

→

a(a(b(a(c(c(a(a(b(x1)))))))))

(1)

Prove or disprove termination.

No.

The following loop proves nontermination.

t₀	=	a(a(b(a(c(c(a(a(b(a(a(x1)))))))))))
	→	a(a(b(a(c(a(a(b(a(c(c(a(a(b(a(x1)))))))))))))))
	→	a(a(b(a(a(a(b(a(c(c(a(a(b(c(c(a(a(b(a(x1)))))))))))))))))))
	→	a(a(b(a(a(a(b(a(c(c(a(a(b(c(a(a(b(a(c(c(a(a(b(x1)))))))))))))))))))))))
	→	a(a(b(a(a(a(b(a(c(c(a(a(b(a(a(b(a(c(c(a(a(b(c(c(a(a(b(x1)))))))))))))))))))))))))))
	=	t₄

where t₄ = C[t₀σ] and σ = {x1/b(a(c(c(a(a(b(c(c(a(a(b(x1))))))))))))} and C = a(a(b(a(☐))))