Left Termination of the query pattern p2(f) w.r.t. the given Prolog program could not be shown:



PROLOG
  ↳ UnrequestedClauseRemoverProof

p11(f1(X)) :- p11(X).
p21(f1(X)) :- p21(X).


The clause

p11(f1(X)) :- p11(X).

can be ignored, as it is not needed by any of the given querys.

Deleting this clauses results in the following prolog program:

p21(f1(X)) :- p21(X).



↳ PROLOG
  ↳ UnrequestedClauseRemoverProof
PROLOG
      ↳ PrologToPiTRSProof
      ↳ PrologToPiTRSProof

p21(f1(X)) :- p21(X).


With regard to the inferred argument filtering the predicates were used in the following modes:
p21: (f)
Transforming PROLOG into the following Term Rewriting System:
Pi-finite rewrite system:
The TRS R consists of the following rules:


p2_1_in_a1(f_11(X)) -> if_p2_1_in_1_a2(X, p2_1_in_a1(X))
if_p2_1_in_1_a2(X, p2_1_out_a1(X)) -> p2_1_out_a1(f_11(X))

The argument filtering Pi contains the following mapping:
p2_1_in_a1(x1)  =  p2_1_in_a
f_11(x1)  =  f_11(x1)
if_p2_1_in_1_a2(x1, x2)  =  if_p2_1_in_1_a1(x2)
p2_1_out_a1(x1)  =  p2_1_out_a1(x1)

Infinitary Constructor Rewriting Termination of PiTRS implies Termination of PROLOG



↳ PROLOG
  ↳ UnrequestedClauseRemoverProof
    ↳ PROLOG
      ↳ PrologToPiTRSProof
PiTRS
          ↳ DependencyPairsProof
      ↳ PrologToPiTRSProof

Pi-finite rewrite system:
The TRS R consists of the following rules:

p2_1_in_a1(f_11(X)) -> if_p2_1_in_1_a2(X, p2_1_in_a1(X))
if_p2_1_in_1_a2(X, p2_1_out_a1(X)) -> p2_1_out_a1(f_11(X))

The argument filtering Pi contains the following mapping:
p2_1_in_a1(x1)  =  p2_1_in_a
f_11(x1)  =  f_11(x1)
if_p2_1_in_1_a2(x1, x2)  =  if_p2_1_in_1_a1(x2)
p2_1_out_a1(x1)  =  p2_1_out_a1(x1)


Pi DP problem:
The TRS P consists of the following rules:

P2_1_IN_A1(f_11(X)) -> IF_P2_1_IN_1_A2(X, p2_1_in_a1(X))
P2_1_IN_A1(f_11(X)) -> P2_1_IN_A1(X)

The TRS R consists of the following rules:

p2_1_in_a1(f_11(X)) -> if_p2_1_in_1_a2(X, p2_1_in_a1(X))
if_p2_1_in_1_a2(X, p2_1_out_a1(X)) -> p2_1_out_a1(f_11(X))

The argument filtering Pi contains the following mapping:
p2_1_in_a1(x1)  =  p2_1_in_a
f_11(x1)  =  f_11(x1)
if_p2_1_in_1_a2(x1, x2)  =  if_p2_1_in_1_a1(x2)
p2_1_out_a1(x1)  =  p2_1_out_a1(x1)
IF_P2_1_IN_1_A2(x1, x2)  =  IF_P2_1_IN_1_A1(x2)
P2_1_IN_A1(x1)  =  P2_1_IN_A

We have to consider all (P,R,Pi)-chains

↳ PROLOG
  ↳ UnrequestedClauseRemoverProof
    ↳ PROLOG
      ↳ PrologToPiTRSProof
        ↳ PiTRS
          ↳ DependencyPairsProof
PiDP
              ↳ DependencyGraphProof
      ↳ PrologToPiTRSProof

Pi DP problem:
The TRS P consists of the following rules:

P2_1_IN_A1(f_11(X)) -> IF_P2_1_IN_1_A2(X, p2_1_in_a1(X))
P2_1_IN_A1(f_11(X)) -> P2_1_IN_A1(X)

The TRS R consists of the following rules:

p2_1_in_a1(f_11(X)) -> if_p2_1_in_1_a2(X, p2_1_in_a1(X))
if_p2_1_in_1_a2(X, p2_1_out_a1(X)) -> p2_1_out_a1(f_11(X))

The argument filtering Pi contains the following mapping:
p2_1_in_a1(x1)  =  p2_1_in_a
f_11(x1)  =  f_11(x1)
if_p2_1_in_1_a2(x1, x2)  =  if_p2_1_in_1_a1(x2)
p2_1_out_a1(x1)  =  p2_1_out_a1(x1)
IF_P2_1_IN_1_A2(x1, x2)  =  IF_P2_1_IN_1_A1(x2)
P2_1_IN_A1(x1)  =  P2_1_IN_A

We have to consider all (P,R,Pi)-chains
The approximation of the Dependency Graph contains 1 SCC with 1 less node.

↳ PROLOG
  ↳ UnrequestedClauseRemoverProof
    ↳ PROLOG
      ↳ PrologToPiTRSProof
        ↳ PiTRS
          ↳ DependencyPairsProof
            ↳ PiDP
              ↳ DependencyGraphProof
PiDP
                  ↳ UsableRulesProof
      ↳ PrologToPiTRSProof

Pi DP problem:
The TRS P consists of the following rules:

P2_1_IN_A1(f_11(X)) -> P2_1_IN_A1(X)

The TRS R consists of the following rules:

p2_1_in_a1(f_11(X)) -> if_p2_1_in_1_a2(X, p2_1_in_a1(X))
if_p2_1_in_1_a2(X, p2_1_out_a1(X)) -> p2_1_out_a1(f_11(X))

The argument filtering Pi contains the following mapping:
p2_1_in_a1(x1)  =  p2_1_in_a
f_11(x1)  =  f_11(x1)
if_p2_1_in_1_a2(x1, x2)  =  if_p2_1_in_1_a1(x2)
p2_1_out_a1(x1)  =  p2_1_out_a1(x1)
P2_1_IN_A1(x1)  =  P2_1_IN_A

We have to consider all (P,R,Pi)-chains
For (infinitary) constructor rewriting we can delete all non-usable rules from R.

↳ PROLOG
  ↳ UnrequestedClauseRemoverProof
    ↳ PROLOG
      ↳ PrologToPiTRSProof
        ↳ PiTRS
          ↳ DependencyPairsProof
            ↳ PiDP
              ↳ DependencyGraphProof
                ↳ PiDP
                  ↳ UsableRulesProof
PiDP
                      ↳ PiDPToQDPProof
      ↳ PrologToPiTRSProof

Pi DP problem:
The TRS P consists of the following rules:

P2_1_IN_A1(f_11(X)) -> P2_1_IN_A1(X)

R is empty.
The argument filtering Pi contains the following mapping:
f_11(x1)  =  f_11(x1)
P2_1_IN_A1(x1)  =  P2_1_IN_A

We have to consider all (P,R,Pi)-chains
Transforming (infinitary) constructor rewriting Pi-DP problem into ordinary QDP problem by application of Pi.

↳ PROLOG
  ↳ UnrequestedClauseRemoverProof
    ↳ PROLOG
      ↳ PrologToPiTRSProof
        ↳ PiTRS
          ↳ DependencyPairsProof
            ↳ PiDP
              ↳ DependencyGraphProof
                ↳ PiDP
                  ↳ UsableRulesProof
                    ↳ PiDP
                      ↳ PiDPToQDPProof
QDP
      ↳ PrologToPiTRSProof

Q DP problem:
The TRS P consists of the following rules:

P2_1_IN_A -> P2_1_IN_A

R is empty.
Q is empty.
We have to consider all (P,Q,R)-chains.
The head symbols of this DP problem are {P2_1_IN_A}.
With regard to the inferred argument filtering the predicates were used in the following modes:
p21: (f)
Transforming PROLOG into the following Term Rewriting System:
Pi-finite rewrite system:
The TRS R consists of the following rules:

p2_1_in_a1(f_11(X)) -> if_p2_1_in_1_a2(X, p2_1_in_a1(X))
if_p2_1_in_1_a2(X, p2_1_out_a1(X)) -> p2_1_out_a1(f_11(X))

The argument filtering Pi contains the following mapping:
p2_1_in_a1(x1)  =  p2_1_in_a
f_11(x1)  =  f_11(x1)
if_p2_1_in_1_a2(x1, x2)  =  if_p2_1_in_1_a1(x2)
p2_1_out_a1(x1)  =  p2_1_out_a1(x1)

Infinitary Constructor Rewriting Termination of PiTRS implies Termination of PROLOG



↳ PROLOG
  ↳ UnrequestedClauseRemoverProof
    ↳ PROLOG
      ↳ PrologToPiTRSProof
      ↳ PrologToPiTRSProof
PiTRS
          ↳ DependencyPairsProof

Pi-finite rewrite system:
The TRS R consists of the following rules:

p2_1_in_a1(f_11(X)) -> if_p2_1_in_1_a2(X, p2_1_in_a1(X))
if_p2_1_in_1_a2(X, p2_1_out_a1(X)) -> p2_1_out_a1(f_11(X))

The argument filtering Pi contains the following mapping:
p2_1_in_a1(x1)  =  p2_1_in_a
f_11(x1)  =  f_11(x1)
if_p2_1_in_1_a2(x1, x2)  =  if_p2_1_in_1_a1(x2)
p2_1_out_a1(x1)  =  p2_1_out_a1(x1)


Pi DP problem:
The TRS P consists of the following rules:

P2_1_IN_A1(f_11(X)) -> IF_P2_1_IN_1_A2(X, p2_1_in_a1(X))
P2_1_IN_A1(f_11(X)) -> P2_1_IN_A1(X)

The TRS R consists of the following rules:

p2_1_in_a1(f_11(X)) -> if_p2_1_in_1_a2(X, p2_1_in_a1(X))
if_p2_1_in_1_a2(X, p2_1_out_a1(X)) -> p2_1_out_a1(f_11(X))

The argument filtering Pi contains the following mapping:
p2_1_in_a1(x1)  =  p2_1_in_a
f_11(x1)  =  f_11(x1)
if_p2_1_in_1_a2(x1, x2)  =  if_p2_1_in_1_a1(x2)
p2_1_out_a1(x1)  =  p2_1_out_a1(x1)
IF_P2_1_IN_1_A2(x1, x2)  =  IF_P2_1_IN_1_A1(x2)
P2_1_IN_A1(x1)  =  P2_1_IN_A

We have to consider all (P,R,Pi)-chains

↳ PROLOG
  ↳ UnrequestedClauseRemoverProof
    ↳ PROLOG
      ↳ PrologToPiTRSProof
      ↳ PrologToPiTRSProof
        ↳ PiTRS
          ↳ DependencyPairsProof
PiDP
              ↳ DependencyGraphProof

Pi DP problem:
The TRS P consists of the following rules:

P2_1_IN_A1(f_11(X)) -> IF_P2_1_IN_1_A2(X, p2_1_in_a1(X))
P2_1_IN_A1(f_11(X)) -> P2_1_IN_A1(X)

The TRS R consists of the following rules:

p2_1_in_a1(f_11(X)) -> if_p2_1_in_1_a2(X, p2_1_in_a1(X))
if_p2_1_in_1_a2(X, p2_1_out_a1(X)) -> p2_1_out_a1(f_11(X))

The argument filtering Pi contains the following mapping:
p2_1_in_a1(x1)  =  p2_1_in_a
f_11(x1)  =  f_11(x1)
if_p2_1_in_1_a2(x1, x2)  =  if_p2_1_in_1_a1(x2)
p2_1_out_a1(x1)  =  p2_1_out_a1(x1)
IF_P2_1_IN_1_A2(x1, x2)  =  IF_P2_1_IN_1_A1(x2)
P2_1_IN_A1(x1)  =  P2_1_IN_A

We have to consider all (P,R,Pi)-chains
The approximation of the Dependency Graph contains 1 SCC with 1 less node.

↳ PROLOG
  ↳ UnrequestedClauseRemoverProof
    ↳ PROLOG
      ↳ PrologToPiTRSProof
      ↳ PrologToPiTRSProof
        ↳ PiTRS
          ↳ DependencyPairsProof
            ↳ PiDP
              ↳ DependencyGraphProof
PiDP
                  ↳ UsableRulesProof

Pi DP problem:
The TRS P consists of the following rules:

P2_1_IN_A1(f_11(X)) -> P2_1_IN_A1(X)

The TRS R consists of the following rules:

p2_1_in_a1(f_11(X)) -> if_p2_1_in_1_a2(X, p2_1_in_a1(X))
if_p2_1_in_1_a2(X, p2_1_out_a1(X)) -> p2_1_out_a1(f_11(X))

The argument filtering Pi contains the following mapping:
p2_1_in_a1(x1)  =  p2_1_in_a
f_11(x1)  =  f_11(x1)
if_p2_1_in_1_a2(x1, x2)  =  if_p2_1_in_1_a1(x2)
p2_1_out_a1(x1)  =  p2_1_out_a1(x1)
P2_1_IN_A1(x1)  =  P2_1_IN_A

We have to consider all (P,R,Pi)-chains
For (infinitary) constructor rewriting we can delete all non-usable rules from R.

↳ PROLOG
  ↳ UnrequestedClauseRemoverProof
    ↳ PROLOG
      ↳ PrologToPiTRSProof
      ↳ PrologToPiTRSProof
        ↳ PiTRS
          ↳ DependencyPairsProof
            ↳ PiDP
              ↳ DependencyGraphProof
                ↳ PiDP
                  ↳ UsableRulesProof
PiDP
                      ↳ PiDPToQDPProof

Pi DP problem:
The TRS P consists of the following rules:

P2_1_IN_A1(f_11(X)) -> P2_1_IN_A1(X)

R is empty.
The argument filtering Pi contains the following mapping:
f_11(x1)  =  f_11(x1)
P2_1_IN_A1(x1)  =  P2_1_IN_A

We have to consider all (P,R,Pi)-chains
Transforming (infinitary) constructor rewriting Pi-DP problem into ordinary QDP problem by application of Pi.

↳ PROLOG
  ↳ UnrequestedClauseRemoverProof
    ↳ PROLOG
      ↳ PrologToPiTRSProof
      ↳ PrologToPiTRSProof
        ↳ PiTRS
          ↳ DependencyPairsProof
            ↳ PiDP
              ↳ DependencyGraphProof
                ↳ PiDP
                  ↳ UsableRulesProof
                    ↳ PiDP
                      ↳ PiDPToQDPProof
QDP

Q DP problem:
The TRS P consists of the following rules:

P2_1_IN_A -> P2_1_IN_A

R is empty.
Q is empty.
We have to consider all (P,Q,R)-chains.
The head symbols of this DP problem are {P2_1_IN_A}.