(0) Obligation:
Q restricted rewrite system:
The TRS R consists of the following rules:
a__from(X) → cons(mark(X), from(s(X)))
a__after(0, XS) → mark(XS)
a__after(s(N), cons(X, XS)) → a__after(mark(N), mark(XS))
mark(from(X)) → a__from(mark(X))
mark(after(X1, X2)) → a__after(mark(X1), mark(X2))
mark(cons(X1, X2)) → cons(mark(X1), X2)
mark(s(X)) → s(mark(X))
mark(0) → 0
a__from(X) → from(X)
a__after(X1, X2) → after(X1, X2)
Q is empty.
(1) DependencyPairsProof (EQUIVALENT transformation)
Using Dependency Pairs [AG00,LPAR04] we result in the following initial DP problem.
(2) Obligation:
Q DP problem:
The TRS P consists of the following rules:
A__FROM(X) → MARK(X)
A__AFTER(0, XS) → MARK(XS)
A__AFTER(s(N), cons(X, XS)) → A__AFTER(mark(N), mark(XS))
A__AFTER(s(N), cons(X, XS)) → MARK(N)
A__AFTER(s(N), cons(X, XS)) → MARK(XS)
MARK(from(X)) → A__FROM(mark(X))
MARK(from(X)) → MARK(X)
MARK(after(X1, X2)) → A__AFTER(mark(X1), mark(X2))
MARK(after(X1, X2)) → MARK(X1)
MARK(after(X1, X2)) → MARK(X2)
MARK(cons(X1, X2)) → MARK(X1)
MARK(s(X)) → MARK(X)
The TRS R consists of the following rules:
a__from(X) → cons(mark(X), from(s(X)))
a__after(0, XS) → mark(XS)
a__after(s(N), cons(X, XS)) → a__after(mark(N), mark(XS))
mark(from(X)) → a__from(mark(X))
mark(after(X1, X2)) → a__after(mark(X1), mark(X2))
mark(cons(X1, X2)) → cons(mark(X1), X2)
mark(s(X)) → s(mark(X))
mark(0) → 0
a__from(X) → from(X)
a__after(X1, X2) → after(X1, X2)
Q is empty.
We have to consider all minimal (P,Q,R)-chains.
(3) QDPOrderProof (EQUIVALENT transformation)
We use the reduction pair processor [LPAR04].
The following pairs can be oriented strictly and are deleted.
A__AFTER(0, XS) → MARK(XS)
The remaining pairs can at least be oriented weakly.
Used ordering: Matrix interpretation [MATRO] with arctic natural numbers [ARCTIC]:
POL(A__FROM(x1)) = | 1A | + | 0A | · | x1 |
POL(MARK(x1)) = | 1A | + | 0A | · | x1 |
POL(A__AFTER(x1, x2)) = | -I | + | 1A | · | x1 | + | 1A | · | x2 |
POL(cons(x1, x2)) = | 0A | + | 0A | · | x1 | + | 0A | · | x2 |
POL(mark(x1)) = | 0A | + | 0A | · | x1 |
POL(from(x1)) = | -I | + | 0A | · | x1 |
POL(after(x1, x2)) = | 1A | + | 1A | · | x1 | + | 1A | · | x2 |
POL(a__from(x1)) = | 0A | + | 0A | · | x1 |
POL(a__after(x1, x2)) = | 1A | + | 1A | · | x1 | + | 1A | · | x2 |
The following usable rules [FROCOS05] were oriented:
a__from(X) → cons(mark(X), from(s(X)))
a__after(s(N), cons(X, XS)) → a__after(mark(N), mark(XS))
mark(after(X1, X2)) → a__after(mark(X1), mark(X2))
a__after(0, XS) → mark(XS)
mark(from(X)) → a__from(mark(X))
mark(s(X)) → s(mark(X))
mark(cons(X1, X2)) → cons(mark(X1), X2)
a__after(X1, X2) → after(X1, X2)
mark(0) → 0
a__from(X) → from(X)
(4) Obligation:
Q DP problem:
The TRS P consists of the following rules:
A__FROM(X) → MARK(X)
A__AFTER(s(N), cons(X, XS)) → A__AFTER(mark(N), mark(XS))
A__AFTER(s(N), cons(X, XS)) → MARK(N)
A__AFTER(s(N), cons(X, XS)) → MARK(XS)
MARK(from(X)) → A__FROM(mark(X))
MARK(from(X)) → MARK(X)
MARK(after(X1, X2)) → A__AFTER(mark(X1), mark(X2))
MARK(after(X1, X2)) → MARK(X1)
MARK(after(X1, X2)) → MARK(X2)
MARK(cons(X1, X2)) → MARK(X1)
MARK(s(X)) → MARK(X)
The TRS R consists of the following rules:
a__from(X) → cons(mark(X), from(s(X)))
a__after(0, XS) → mark(XS)
a__after(s(N), cons(X, XS)) → a__after(mark(N), mark(XS))
mark(from(X)) → a__from(mark(X))
mark(after(X1, X2)) → a__after(mark(X1), mark(X2))
mark(cons(X1, X2)) → cons(mark(X1), X2)
mark(s(X)) → s(mark(X))
mark(0) → 0
a__from(X) → from(X)
a__after(X1, X2) → after(X1, X2)
Q is empty.
We have to consider all minimal (P,Q,R)-chains.
(5) QDPOrderProof (EQUIVALENT transformation)
We use the reduction pair processor [LPAR04].
The following pairs can be oriented strictly and are deleted.
MARK(after(X1, X2)) → MARK(X2)
The remaining pairs can at least be oriented weakly.
Used ordering: Matrix interpretation [MATRO] with arctic natural numbers [ARCTIC]:
POL(A__FROM(x1)) = | 1A | + | 0A | · | x1 |
POL(MARK(x1)) = | 1A | + | 0A | · | x1 |
POL(A__AFTER(x1, x2)) = | 5A | + | 0A | · | x1 | + | 0A | · | x2 |
POL(cons(x1, x2)) = | 0A | + | 0A | · | x1 | + | 0A | · | x2 |
POL(mark(x1)) = | 0A | + | 0A | · | x1 |
POL(from(x1)) = | 0A | + | 0A | · | x1 |
POL(after(x1, x2)) = | 5A | + | 0A | · | x1 | + | 1A | · | x2 |
POL(a__from(x1)) = | 0A | + | 0A | · | x1 |
POL(a__after(x1, x2)) = | 5A | + | 0A | · | x1 | + | 1A | · | x2 |
The following usable rules [FROCOS05] were oriented:
a__from(X) → cons(mark(X), from(s(X)))
a__after(s(N), cons(X, XS)) → a__after(mark(N), mark(XS))
mark(after(X1, X2)) → a__after(mark(X1), mark(X2))
a__after(0, XS) → mark(XS)
mark(from(X)) → a__from(mark(X))
mark(s(X)) → s(mark(X))
mark(cons(X1, X2)) → cons(mark(X1), X2)
a__after(X1, X2) → after(X1, X2)
mark(0) → 0
a__from(X) → from(X)
(6) Obligation:
Q DP problem:
The TRS P consists of the following rules:
A__FROM(X) → MARK(X)
A__AFTER(s(N), cons(X, XS)) → A__AFTER(mark(N), mark(XS))
A__AFTER(s(N), cons(X, XS)) → MARK(N)
A__AFTER(s(N), cons(X, XS)) → MARK(XS)
MARK(from(X)) → A__FROM(mark(X))
MARK(from(X)) → MARK(X)
MARK(after(X1, X2)) → A__AFTER(mark(X1), mark(X2))
MARK(after(X1, X2)) → MARK(X1)
MARK(cons(X1, X2)) → MARK(X1)
MARK(s(X)) → MARK(X)
The TRS R consists of the following rules:
a__from(X) → cons(mark(X), from(s(X)))
a__after(0, XS) → mark(XS)
a__after(s(N), cons(X, XS)) → a__after(mark(N), mark(XS))
mark(from(X)) → a__from(mark(X))
mark(after(X1, X2)) → a__after(mark(X1), mark(X2))
mark(cons(X1, X2)) → cons(mark(X1), X2)
mark(s(X)) → s(mark(X))
mark(0) → 0
a__from(X) → from(X)
a__after(X1, X2) → after(X1, X2)
Q is empty.
We have to consider all minimal (P,Q,R)-chains.
(7) QDPOrderProof (EQUIVALENT transformation)
We use the reduction pair processor [LPAR04].
The following pairs can be oriented strictly and are deleted.
MARK(from(X)) → MARK(X)
The remaining pairs can at least be oriented weakly.
Used ordering: Matrix interpretation [MATRO] with arctic natural numbers [ARCTIC]:
POL(A__FROM(x1)) = | 1A | + | 0A | · | x1 |
POL(MARK(x1)) = | -I | + | 0A | · | x1 |
POL(A__AFTER(x1, x2)) = | -I | + | 0A | · | x1 | + | 0A | · | x2 |
POL(cons(x1, x2)) = | 0A | + | 0A | · | x1 | + | 0A | · | x2 |
POL(mark(x1)) = | 0A | + | 0A | · | x1 |
POL(from(x1)) = | 1A | + | 1A | · | x1 |
POL(after(x1, x2)) = | 0A | + | 0A | · | x1 | + | 0A | · | x2 |
POL(a__from(x1)) = | 1A | + | 1A | · | x1 |
POL(a__after(x1, x2)) = | 0A | + | 0A | · | x1 | + | 0A | · | x2 |
The following usable rules [FROCOS05] were oriented:
a__from(X) → cons(mark(X), from(s(X)))
a__after(s(N), cons(X, XS)) → a__after(mark(N), mark(XS))
mark(after(X1, X2)) → a__after(mark(X1), mark(X2))
a__after(0, XS) → mark(XS)
mark(from(X)) → a__from(mark(X))
mark(s(X)) → s(mark(X))
mark(cons(X1, X2)) → cons(mark(X1), X2)
a__after(X1, X2) → after(X1, X2)
mark(0) → 0
a__from(X) → from(X)
(8) Obligation:
Q DP problem:
The TRS P consists of the following rules:
A__FROM(X) → MARK(X)
A__AFTER(s(N), cons(X, XS)) → A__AFTER(mark(N), mark(XS))
A__AFTER(s(N), cons(X, XS)) → MARK(N)
A__AFTER(s(N), cons(X, XS)) → MARK(XS)
MARK(from(X)) → A__FROM(mark(X))
MARK(after(X1, X2)) → A__AFTER(mark(X1), mark(X2))
MARK(after(X1, X2)) → MARK(X1)
MARK(cons(X1, X2)) → MARK(X1)
MARK(s(X)) → MARK(X)
The TRS R consists of the following rules:
a__from(X) → cons(mark(X), from(s(X)))
a__after(0, XS) → mark(XS)
a__after(s(N), cons(X, XS)) → a__after(mark(N), mark(XS))
mark(from(X)) → a__from(mark(X))
mark(after(X1, X2)) → a__after(mark(X1), mark(X2))
mark(cons(X1, X2)) → cons(mark(X1), X2)
mark(s(X)) → s(mark(X))
mark(0) → 0
a__from(X) → from(X)
a__after(X1, X2) → after(X1, X2)
Q is empty.
We have to consider all minimal (P,Q,R)-chains.
(9) QDPOrderProof (EQUIVALENT transformation)
We use the reduction pair processor [LPAR04].
The following pairs can be oriented strictly and are deleted.
MARK(after(X1, X2)) → MARK(X1)
The remaining pairs can at least be oriented weakly.
Used ordering: Matrix interpretation [MATRO] with arctic natural numbers [ARCTIC]:
POL(A__FROM(x1)) = | -I | + | 0A | · | x1 |
POL(MARK(x1)) = | -I | + | 0A | · | x1 |
POL(A__AFTER(x1, x2)) = | 0A | + | 0A | · | x1 | + | 0A | · | x2 |
POL(cons(x1, x2)) = | -I | + | 0A | · | x1 | + | 0A | · | x2 |
POL(mark(x1)) = | -I | + | 0A | · | x1 |
POL(from(x1)) = | -I | + | 0A | · | x1 |
POL(after(x1, x2)) = | 0A | + | 4A | · | x1 | + | 1A | · | x2 |
POL(a__from(x1)) = | -I | + | 0A | · | x1 |
POL(a__after(x1, x2)) = | 0A | + | 4A | · | x1 | + | 1A | · | x2 |
The following usable rules [FROCOS05] were oriented:
a__from(X) → cons(mark(X), from(s(X)))
a__after(s(N), cons(X, XS)) → a__after(mark(N), mark(XS))
mark(after(X1, X2)) → a__after(mark(X1), mark(X2))
a__after(0, XS) → mark(XS)
mark(from(X)) → a__from(mark(X))
mark(s(X)) → s(mark(X))
mark(cons(X1, X2)) → cons(mark(X1), X2)
a__after(X1, X2) → after(X1, X2)
mark(0) → 0
a__from(X) → from(X)
(10) Obligation:
Q DP problem:
The TRS P consists of the following rules:
A__FROM(X) → MARK(X)
A__AFTER(s(N), cons(X, XS)) → A__AFTER(mark(N), mark(XS))
A__AFTER(s(N), cons(X, XS)) → MARK(N)
A__AFTER(s(N), cons(X, XS)) → MARK(XS)
MARK(from(X)) → A__FROM(mark(X))
MARK(after(X1, X2)) → A__AFTER(mark(X1), mark(X2))
MARK(cons(X1, X2)) → MARK(X1)
MARK(s(X)) → MARK(X)
The TRS R consists of the following rules:
a__from(X) → cons(mark(X), from(s(X)))
a__after(0, XS) → mark(XS)
a__after(s(N), cons(X, XS)) → a__after(mark(N), mark(XS))
mark(from(X)) → a__from(mark(X))
mark(after(X1, X2)) → a__after(mark(X1), mark(X2))
mark(cons(X1, X2)) → cons(mark(X1), X2)
mark(s(X)) → s(mark(X))
mark(0) → 0
a__from(X) → from(X)
a__after(X1, X2) → after(X1, X2)
Q is empty.
We have to consider all minimal (P,Q,R)-chains.
(11) QDPOrderProof (EQUIVALENT transformation)
We use the reduction pair processor [LPAR04].
The following pairs can be oriented strictly and are deleted.
MARK(after(X1, X2)) → A__AFTER(mark(X1), mark(X2))
The remaining pairs can at least be oriented weakly.
Used ordering: Matrix interpretation [MATRO] with arctic natural numbers [ARCTIC]:
POL(A__FROM(x1)) = | 0A | + | 0A | · | x1 |
POL(MARK(x1)) = | 0A | + | 0A | · | x1 |
POL(A__AFTER(x1, x2)) = | 0A | + | 0A | · | x1 | + | 0A | · | x2 |
POL(cons(x1, x2)) = | 0A | + | 0A | · | x1 | + | 0A | · | x2 |
POL(mark(x1)) = | 0A | + | 0A | · | x1 |
POL(from(x1)) = | -I | + | 0A | · | x1 |
POL(after(x1, x2)) = | 1A | + | 1A | · | x1 | + | 1A | · | x2 |
POL(a__from(x1)) = | 0A | + | 0A | · | x1 |
POL(a__after(x1, x2)) = | 1A | + | 1A | · | x1 | + | 1A | · | x2 |
The following usable rules [FROCOS05] were oriented:
a__from(X) → cons(mark(X), from(s(X)))
a__after(s(N), cons(X, XS)) → a__after(mark(N), mark(XS))
mark(after(X1, X2)) → a__after(mark(X1), mark(X2))
a__after(0, XS) → mark(XS)
mark(from(X)) → a__from(mark(X))
mark(s(X)) → s(mark(X))
mark(cons(X1, X2)) → cons(mark(X1), X2)
a__after(X1, X2) → after(X1, X2)
mark(0) → 0
a__from(X) → from(X)
(12) Obligation:
Q DP problem:
The TRS P consists of the following rules:
A__FROM(X) → MARK(X)
A__AFTER(s(N), cons(X, XS)) → A__AFTER(mark(N), mark(XS))
A__AFTER(s(N), cons(X, XS)) → MARK(N)
A__AFTER(s(N), cons(X, XS)) → MARK(XS)
MARK(from(X)) → A__FROM(mark(X))
MARK(cons(X1, X2)) → MARK(X1)
MARK(s(X)) → MARK(X)
The TRS R consists of the following rules:
a__from(X) → cons(mark(X), from(s(X)))
a__after(0, XS) → mark(XS)
a__after(s(N), cons(X, XS)) → a__after(mark(N), mark(XS))
mark(from(X)) → a__from(mark(X))
mark(after(X1, X2)) → a__after(mark(X1), mark(X2))
mark(cons(X1, X2)) → cons(mark(X1), X2)
mark(s(X)) → s(mark(X))
mark(0) → 0
a__from(X) → from(X)
a__after(X1, X2) → after(X1, X2)
Q is empty.
We have to consider all minimal (P,Q,R)-chains.
(13) DependencyGraphProof (EQUIVALENT transformation)
The approximation of the Dependency Graph [LPAR04,FROCOS05,EDGSTAR] contains 2 SCCs with 2 less nodes.
(14) Complex Obligation (AND)
(15) Obligation:
Q DP problem:
The TRS P consists of the following rules:
MARK(from(X)) → A__FROM(mark(X))
A__FROM(X) → MARK(X)
MARK(cons(X1, X2)) → MARK(X1)
MARK(s(X)) → MARK(X)
The TRS R consists of the following rules:
a__from(X) → cons(mark(X), from(s(X)))
a__after(0, XS) → mark(XS)
a__after(s(N), cons(X, XS)) → a__after(mark(N), mark(XS))
mark(from(X)) → a__from(mark(X))
mark(after(X1, X2)) → a__after(mark(X1), mark(X2))
mark(cons(X1, X2)) → cons(mark(X1), X2)
mark(s(X)) → s(mark(X))
mark(0) → 0
a__from(X) → from(X)
a__after(X1, X2) → after(X1, X2)
Q is empty.
We have to consider all minimal (P,Q,R)-chains.
(16) QDPOrderProof (EQUIVALENT transformation)
We use the reduction pair processor [LPAR04].
The following pairs can be oriented strictly and are deleted.
MARK(from(X)) → A__FROM(mark(X))
The remaining pairs can at least be oriented weakly.
Used ordering: Matrix interpretation [MATRO] with arctic natural numbers [ARCTIC]:
POL(MARK(x1)) = | -I | + | 0A | · | x1 |
POL(from(x1)) = | -I | + | 1A | · | x1 |
POL(A__FROM(x1)) = | -I | + | 0A | · | x1 |
POL(mark(x1)) = | -I | + | 0A | · | x1 |
POL(cons(x1, x2)) = | -I | + | 0A | · | x1 | + | 0A | · | x2 |
POL(a__from(x1)) = | -I | + | 1A | · | x1 |
POL(a__after(x1, x2)) = | -I | + | 0A | · | x1 | + | 0A | · | x2 |
POL(after(x1, x2)) = | -I | + | 0A | · | x1 | + | 0A | · | x2 |
The following usable rules [FROCOS05] were oriented:
a__from(X) → cons(mark(X), from(s(X)))
a__after(s(N), cons(X, XS)) → a__after(mark(N), mark(XS))
mark(after(X1, X2)) → a__after(mark(X1), mark(X2))
a__after(0, XS) → mark(XS)
mark(from(X)) → a__from(mark(X))
mark(s(X)) → s(mark(X))
mark(cons(X1, X2)) → cons(mark(X1), X2)
a__after(X1, X2) → after(X1, X2)
mark(0) → 0
a__from(X) → from(X)
(17) Obligation:
Q DP problem:
The TRS P consists of the following rules:
A__FROM(X) → MARK(X)
MARK(cons(X1, X2)) → MARK(X1)
MARK(s(X)) → MARK(X)
The TRS R consists of the following rules:
a__from(X) → cons(mark(X), from(s(X)))
a__after(0, XS) → mark(XS)
a__after(s(N), cons(X, XS)) → a__after(mark(N), mark(XS))
mark(from(X)) → a__from(mark(X))
mark(after(X1, X2)) → a__after(mark(X1), mark(X2))
mark(cons(X1, X2)) → cons(mark(X1), X2)
mark(s(X)) → s(mark(X))
mark(0) → 0
a__from(X) → from(X)
a__after(X1, X2) → after(X1, X2)
Q is empty.
We have to consider all minimal (P,Q,R)-chains.
(18) DependencyGraphProof (EQUIVALENT transformation)
The approximation of the Dependency Graph [LPAR04,FROCOS05,EDGSTAR] contains 1 SCC with 1 less node.
(19) Obligation:
Q DP problem:
The TRS P consists of the following rules:
MARK(s(X)) → MARK(X)
MARK(cons(X1, X2)) → MARK(X1)
The TRS R consists of the following rules:
a__from(X) → cons(mark(X), from(s(X)))
a__after(0, XS) → mark(XS)
a__after(s(N), cons(X, XS)) → a__after(mark(N), mark(XS))
mark(from(X)) → a__from(mark(X))
mark(after(X1, X2)) → a__after(mark(X1), mark(X2))
mark(cons(X1, X2)) → cons(mark(X1), X2)
mark(s(X)) → s(mark(X))
mark(0) → 0
a__from(X) → from(X)
a__after(X1, X2) → after(X1, X2)
Q is empty.
We have to consider all minimal (P,Q,R)-chains.
(20) UsableRulesProof (EQUIVALENT transformation)
We can use the usable rules and reduction pair processor [LPAR04] with the Ce-compatible extension of the polynomial order that maps every function symbol to the sum of its arguments. Then, we can delete all non-usable rules [FROCOS05] from R.
(21) Obligation:
Q DP problem:
The TRS P consists of the following rules:
MARK(s(X)) → MARK(X)
MARK(cons(X1, X2)) → MARK(X1)
R is empty.
Q is empty.
We have to consider all minimal (P,Q,R)-chains.
(22) QDPSizeChangeProof (EQUIVALENT transformation)
By using the subterm criterion [SUBTERM_CRITERION] together with the size-change analysis [AAECC05] we have proven that there are no infinite chains for this DP problem.
From the DPs we obtained the following set of size-change graphs:
- MARK(s(X)) → MARK(X)
The graph contains the following edges 1 > 1
- MARK(cons(X1, X2)) → MARK(X1)
The graph contains the following edges 1 > 1
(23) TRUE
(24) Obligation:
Q DP problem:
The TRS P consists of the following rules:
A__AFTER(s(N), cons(X, XS)) → A__AFTER(mark(N), mark(XS))
The TRS R consists of the following rules:
a__from(X) → cons(mark(X), from(s(X)))
a__after(0, XS) → mark(XS)
a__after(s(N), cons(X, XS)) → a__after(mark(N), mark(XS))
mark(from(X)) → a__from(mark(X))
mark(after(X1, X2)) → a__after(mark(X1), mark(X2))
mark(cons(X1, X2)) → cons(mark(X1), X2)
mark(s(X)) → s(mark(X))
mark(0) → 0
a__from(X) → from(X)
a__after(X1, X2) → after(X1, X2)
Q is empty.
We have to consider all minimal (P,Q,R)-chains.
(25) QDPOrderProof (EQUIVALENT transformation)
We use the reduction pair processor [LPAR04].
The following pairs can be oriented strictly and are deleted.
A__AFTER(s(N), cons(X, XS)) → A__AFTER(mark(N), mark(XS))
The remaining pairs can at least be oriented weakly.
Used ordering: Polynomial interpretation [POLO]:
POL(0) = 0
POL(A__AFTER(x1, x2)) = x1
POL(a__after(x1, x2)) = 1 + x2
POL(a__from(x1)) = 0
POL(after(x1, x2)) = 1 + x2
POL(cons(x1, x2)) = x2
POL(from(x1)) = 0
POL(mark(x1)) = x1
POL(s(x1)) = 1 + x1
The following usable rules [FROCOS05] were oriented:
a__from(X) → cons(mark(X), from(s(X)))
a__after(s(N), cons(X, XS)) → a__after(mark(N), mark(XS))
mark(after(X1, X2)) → a__after(mark(X1), mark(X2))
a__after(0, XS) → mark(XS)
mark(from(X)) → a__from(mark(X))
mark(s(X)) → s(mark(X))
mark(cons(X1, X2)) → cons(mark(X1), X2)
a__after(X1, X2) → after(X1, X2)
mark(0) → 0
a__from(X) → from(X)
(26) Obligation:
Q DP problem:
P is empty.
The TRS R consists of the following rules:
a__from(X) → cons(mark(X), from(s(X)))
a__after(0, XS) → mark(XS)
a__after(s(N), cons(X, XS)) → a__after(mark(N), mark(XS))
mark(from(X)) → a__from(mark(X))
mark(after(X1, X2)) → a__after(mark(X1), mark(X2))
mark(cons(X1, X2)) → cons(mark(X1), X2)
mark(s(X)) → s(mark(X))
mark(0) → 0
a__from(X) → from(X)
a__after(X1, X2) → after(X1, X2)
Q is empty.
We have to consider all minimal (P,Q,R)-chains.
(27) PisEmptyProof (EQUIVALENT transformation)
The TRS P is empty. Hence, there is no (P,Q,R) chain.
(28) TRUE