Certification Problem

Input (TPDB TRS_Standard/Transformed_CSR_04/PALINDROME_nosorts-noand_L)

The rewrite relation of the following TRS is considered.

__(__(X,Y),Z) __(X,__(Y,Z)) (1)
__(X,nil) X (2)
__(nil,X) X (3)
U11(tt) U12(tt) (4)
U12(tt) tt (5)
isNePal(__(I,__(P,I))) U11(tt) (6)

Property / Task

Prove or disprove termination.

Answer / Result

Yes.

Proof (by AProVE @ termCOMP 2023)

1 Rule Removal

Using the linear polynomial interpretation over the naturals
[__(x1, x2)] = 2 + 1 · x1 + 1 · x2
[nil] = 2
[U11(x1)] = 2 + 2 · x1
[tt] = 2
[U12(x1)] = 2 · x1
[isNePal(x1)] = 2 · x1
all of the following rules can be deleted.
__(X,nil) X (2)
__(nil,X) X (3)
U11(tt) U12(tt) (4)
U12(tt) tt (5)
isNePal(__(I,__(P,I))) U11(tt) (6)

1.1 Rule Removal

Using the Knuth Bendix order with w0 = 1 and the following precedence and weight functions
prec(__) = 0 weight(__) = 0
all of the following rules can be deleted.
__(__(X,Y),Z) __(X,__(Y,Z)) (1)

1.1.1 R is empty

There are no rules in the TRS. Hence, it is terminating.