YES Termination w.r.t. Q proof of /home/cern_httpd/provide/research/cycsrs/tpdb/TPDB-d9b80194f163/SRS_Standard/Zantema_04/z108.srs

(0) Obligation:

Q restricted rewrite system:
The TRS R consists of the following rules:

a(a(x)) → b(c(x))
b(b(x)) → c(d(x))
c(c(x)) → d(d(d(x)))
d(d(d(x))) → a(c(x))

Q is empty.

(1) QTRSRRRProof (EQUIVALENT transformation)

Used ordering:
Polynomial interpretation [POLO]:

POL(a(x1)) = 30 + x1   
POL(b(x1)) = 27 + x1   
POL(c(x1)) = 32 + x1   
POL(d(x1)) = 21 + x1   
With this ordering the following rules can be removed by the rule removal processor [LPAR04] because they are oriented strictly:

a(a(x)) → b(c(x))
b(b(x)) → c(d(x))
c(c(x)) → d(d(d(x)))
d(d(d(x))) → a(c(x))


(2) Obligation:

Q restricted rewrite system:
R is empty.
Q is empty.

(3) RisEmptyProof (EQUIVALENT transformation)

The TRS R is empty. Hence, termination is trivially proven.

(4) YES