Certification Problem

Input (TPDB SRS_Standard/Waldmann_07_size12/size-12-alpha-3-num-279)

The rewrite relation of the following TRS is considered.

a(x1) x1 (1)
a(b(x1)) c(b(x1)) (2)
b(x1) a(a(c(x1))) (3)
c(c(x1)) b(x1) (4)

Property / Task

Prove or disprove termination.

Answer / Result

Yes.

Proof (by AProVE @ termCOMP 2023)

1 Dependency Pair Transformation

The following set of initial dependency pairs has been identified.
a#(b(x1)) c#(b(x1)) (5)
b#(x1) a#(a(c(x1))) (6)
b#(x1) a#(c(x1)) (7)
b#(x1) c#(x1) (8)
c#(c(x1)) b#(x1) (9)

1.1 Reduction Pair Processor

Using the matrix interpretations of dimension 3 with strict dimension 1 over the arctic semiring over the naturals
[a#(x1)] =
-∞
-∞
-∞
+
0 0 -∞
-∞ -∞ -∞
-∞ -∞ -∞
· x1
[b(x1)] =
-∞
0
0
+
0 0 0
1 1 1
1 1 1
· x1
[c#(x1)] =
-∞
-∞
-∞
+
0 -∞ -∞
-∞ -∞ -∞
-∞ -∞ -∞
· x1
[b#(x1)] =
-∞
-∞
-∞
+
0 0 0
-∞ -∞ -∞
-∞ -∞ -∞
· x1
[a(x1)] =
-∞
-∞
0
+
0 0 -∞
0 0 -∞
0 1 0
· x1
[c(x1)] =
-∞
-∞
0
+
0 0 0
0 0 0
1 1 1
· x1
the pair
a#(b(x1)) c#(b(x1)) (5)
could be deleted.

1.1.1 Dependency Graph Processor

The dependency pairs are split into 1 component.