Termination w.r.t. Q of the following Term Rewriting System could not be shown:

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

from1(X) -> cons2(X, from1(s1(X)))
2ndspos2(0, Z) -> rnil
2ndspos2(s1(N), cons2(X, Z)) -> 2ndspos2(s1(N), cons22(X, Z))
2ndspos2(s1(N), cons22(X, cons2(Y, Z))) -> rcons2(posrecip1(Y), 2ndsneg2(N, Z))
2ndsneg2(0, Z) -> rnil
2ndsneg2(s1(N), cons2(X, Z)) -> 2ndsneg2(s1(N), cons22(X, Z))
2ndsneg2(s1(N), cons22(X, cons2(Y, Z))) -> rcons2(negrecip1(Y), 2ndspos2(N, Z))
pi1(X) -> 2ndspos2(X, from1(0))
plus2(0, Y) -> Y
plus2(s1(X), Y) -> s1(plus2(X, Y))
times2(0, Y) -> 0
times2(s1(X), Y) -> plus2(Y, times2(X, Y))
square1(X) -> times2(X, X)

Q is empty.


QTRS
  ↳ Non-Overlap Check

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

from1(X) -> cons2(X, from1(s1(X)))
2ndspos2(0, Z) -> rnil
2ndspos2(s1(N), cons2(X, Z)) -> 2ndspos2(s1(N), cons22(X, Z))
2ndspos2(s1(N), cons22(X, cons2(Y, Z))) -> rcons2(posrecip1(Y), 2ndsneg2(N, Z))
2ndsneg2(0, Z) -> rnil
2ndsneg2(s1(N), cons2(X, Z)) -> 2ndsneg2(s1(N), cons22(X, Z))
2ndsneg2(s1(N), cons22(X, cons2(Y, Z))) -> rcons2(negrecip1(Y), 2ndspos2(N, Z))
pi1(X) -> 2ndspos2(X, from1(0))
plus2(0, Y) -> Y
plus2(s1(X), Y) -> s1(plus2(X, Y))
times2(0, Y) -> 0
times2(s1(X), Y) -> plus2(Y, times2(X, Y))
square1(X) -> times2(X, X)

Q is empty.

The TRS is non-overlapping. Hence, we can switch to innermost.

↳ QTRS
  ↳ Non-Overlap Check
QTRS
      ↳ DependencyPairsProof

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

from1(X) -> cons2(X, from1(s1(X)))
2ndspos2(0, Z) -> rnil
2ndspos2(s1(N), cons2(X, Z)) -> 2ndspos2(s1(N), cons22(X, Z))
2ndspos2(s1(N), cons22(X, cons2(Y, Z))) -> rcons2(posrecip1(Y), 2ndsneg2(N, Z))
2ndsneg2(0, Z) -> rnil
2ndsneg2(s1(N), cons2(X, Z)) -> 2ndsneg2(s1(N), cons22(X, Z))
2ndsneg2(s1(N), cons22(X, cons2(Y, Z))) -> rcons2(negrecip1(Y), 2ndspos2(N, Z))
pi1(X) -> 2ndspos2(X, from1(0))
plus2(0, Y) -> Y
plus2(s1(X), Y) -> s1(plus2(X, Y))
times2(0, Y) -> 0
times2(s1(X), Y) -> plus2(Y, times2(X, Y))
square1(X) -> times2(X, X)

The set Q consists of the following terms:

from1(x0)
2ndspos2(0, x0)
2ndspos2(s1(x0), cons2(x1, x2))
2ndspos2(s1(x0), cons22(x1, cons2(x2, x3)))
2ndsneg2(0, x0)
2ndsneg2(s1(x0), cons2(x1, x2))
2ndsneg2(s1(x0), cons22(x1, cons2(x2, x3)))
pi1(x0)
plus2(0, x0)
plus2(s1(x0), x1)
times2(0, x0)
times2(s1(x0), x1)
square1(x0)


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

PLUS2(s1(X), Y) -> PLUS2(X, Y)
PI1(X) -> 2NDSPOS2(X, from1(0))
TIMES2(s1(X), Y) -> PLUS2(Y, times2(X, Y))
2NDSNEG2(s1(N), cons2(X, Z)) -> 2NDSNEG2(s1(N), cons22(X, Z))
TIMES2(s1(X), Y) -> TIMES2(X, Y)
2NDSNEG2(s1(N), cons22(X, cons2(Y, Z))) -> 2NDSPOS2(N, Z)
SQUARE1(X) -> TIMES2(X, X)
PI1(X) -> FROM1(0)
2NDSPOS2(s1(N), cons22(X, cons2(Y, Z))) -> 2NDSNEG2(N, Z)
2NDSPOS2(s1(N), cons2(X, Z)) -> 2NDSPOS2(s1(N), cons22(X, Z))
FROM1(X) -> FROM1(s1(X))

The TRS R consists of the following rules:

from1(X) -> cons2(X, from1(s1(X)))
2ndspos2(0, Z) -> rnil
2ndspos2(s1(N), cons2(X, Z)) -> 2ndspos2(s1(N), cons22(X, Z))
2ndspos2(s1(N), cons22(X, cons2(Y, Z))) -> rcons2(posrecip1(Y), 2ndsneg2(N, Z))
2ndsneg2(0, Z) -> rnil
2ndsneg2(s1(N), cons2(X, Z)) -> 2ndsneg2(s1(N), cons22(X, Z))
2ndsneg2(s1(N), cons22(X, cons2(Y, Z))) -> rcons2(negrecip1(Y), 2ndspos2(N, Z))
pi1(X) -> 2ndspos2(X, from1(0))
plus2(0, Y) -> Y
plus2(s1(X), Y) -> s1(plus2(X, Y))
times2(0, Y) -> 0
times2(s1(X), Y) -> plus2(Y, times2(X, Y))
square1(X) -> times2(X, X)

The set Q consists of the following terms:

from1(x0)
2ndspos2(0, x0)
2ndspos2(s1(x0), cons2(x1, x2))
2ndspos2(s1(x0), cons22(x1, cons2(x2, x3)))
2ndsneg2(0, x0)
2ndsneg2(s1(x0), cons2(x1, x2))
2ndsneg2(s1(x0), cons22(x1, cons2(x2, x3)))
pi1(x0)
plus2(0, x0)
plus2(s1(x0), x1)
times2(0, x0)
times2(s1(x0), x1)
square1(x0)

We have to consider all minimal (P,Q,R)-chains.

↳ QTRS
  ↳ Non-Overlap Check
    ↳ QTRS
      ↳ DependencyPairsProof
QDP
          ↳ DependencyGraphProof

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

PLUS2(s1(X), Y) -> PLUS2(X, Y)
PI1(X) -> 2NDSPOS2(X, from1(0))
TIMES2(s1(X), Y) -> PLUS2(Y, times2(X, Y))
2NDSNEG2(s1(N), cons2(X, Z)) -> 2NDSNEG2(s1(N), cons22(X, Z))
TIMES2(s1(X), Y) -> TIMES2(X, Y)
2NDSNEG2(s1(N), cons22(X, cons2(Y, Z))) -> 2NDSPOS2(N, Z)
SQUARE1(X) -> TIMES2(X, X)
PI1(X) -> FROM1(0)
2NDSPOS2(s1(N), cons22(X, cons2(Y, Z))) -> 2NDSNEG2(N, Z)
2NDSPOS2(s1(N), cons2(X, Z)) -> 2NDSPOS2(s1(N), cons22(X, Z))
FROM1(X) -> FROM1(s1(X))

The TRS R consists of the following rules:

from1(X) -> cons2(X, from1(s1(X)))
2ndspos2(0, Z) -> rnil
2ndspos2(s1(N), cons2(X, Z)) -> 2ndspos2(s1(N), cons22(X, Z))
2ndspos2(s1(N), cons22(X, cons2(Y, Z))) -> rcons2(posrecip1(Y), 2ndsneg2(N, Z))
2ndsneg2(0, Z) -> rnil
2ndsneg2(s1(N), cons2(X, Z)) -> 2ndsneg2(s1(N), cons22(X, Z))
2ndsneg2(s1(N), cons22(X, cons2(Y, Z))) -> rcons2(negrecip1(Y), 2ndspos2(N, Z))
pi1(X) -> 2ndspos2(X, from1(0))
plus2(0, Y) -> Y
plus2(s1(X), Y) -> s1(plus2(X, Y))
times2(0, Y) -> 0
times2(s1(X), Y) -> plus2(Y, times2(X, Y))
square1(X) -> times2(X, X)

The set Q consists of the following terms:

from1(x0)
2ndspos2(0, x0)
2ndspos2(s1(x0), cons2(x1, x2))
2ndspos2(s1(x0), cons22(x1, cons2(x2, x3)))
2ndsneg2(0, x0)
2ndsneg2(s1(x0), cons2(x1, x2))
2ndsneg2(s1(x0), cons22(x1, cons2(x2, x3)))
pi1(x0)
plus2(0, x0)
plus2(s1(x0), x1)
times2(0, x0)
times2(s1(x0), x1)
square1(x0)

We have to consider all minimal (P,Q,R)-chains.
The approximation of the Dependency Graph contains 4 SCCs with 4 less nodes.

↳ QTRS
  ↳ Non-Overlap Check
    ↳ QTRS
      ↳ DependencyPairsProof
        ↳ QDP
          ↳ DependencyGraphProof
            ↳ AND
QDP
                ↳ QDPAfsSolverProof
              ↳ QDP
              ↳ QDP
              ↳ QDP

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

PLUS2(s1(X), Y) -> PLUS2(X, Y)

The TRS R consists of the following rules:

from1(X) -> cons2(X, from1(s1(X)))
2ndspos2(0, Z) -> rnil
2ndspos2(s1(N), cons2(X, Z)) -> 2ndspos2(s1(N), cons22(X, Z))
2ndspos2(s1(N), cons22(X, cons2(Y, Z))) -> rcons2(posrecip1(Y), 2ndsneg2(N, Z))
2ndsneg2(0, Z) -> rnil
2ndsneg2(s1(N), cons2(X, Z)) -> 2ndsneg2(s1(N), cons22(X, Z))
2ndsneg2(s1(N), cons22(X, cons2(Y, Z))) -> rcons2(negrecip1(Y), 2ndspos2(N, Z))
pi1(X) -> 2ndspos2(X, from1(0))
plus2(0, Y) -> Y
plus2(s1(X), Y) -> s1(plus2(X, Y))
times2(0, Y) -> 0
times2(s1(X), Y) -> plus2(Y, times2(X, Y))
square1(X) -> times2(X, X)

The set Q consists of the following terms:

from1(x0)
2ndspos2(0, x0)
2ndspos2(s1(x0), cons2(x1, x2))
2ndspos2(s1(x0), cons22(x1, cons2(x2, x3)))
2ndsneg2(0, x0)
2ndsneg2(s1(x0), cons2(x1, x2))
2ndsneg2(s1(x0), cons22(x1, cons2(x2, x3)))
pi1(x0)
plus2(0, x0)
plus2(s1(x0), x1)
times2(0, x0)
times2(s1(x0), x1)
square1(x0)

We have to consider all minimal (P,Q,R)-chains.
By using an argument filtering and a montonic ordering, at least one Dependency Pair of this SCC can be strictly oriented.

PLUS2(s1(X), Y) -> PLUS2(X, Y)
Used argument filtering: PLUS2(x1, x2)  =  x1
s1(x1)  =  s1(x1)
Used ordering: Quasi Precedence: trivial


↳ QTRS
  ↳ Non-Overlap Check
    ↳ QTRS
      ↳ DependencyPairsProof
        ↳ QDP
          ↳ DependencyGraphProof
            ↳ AND
              ↳ QDP
                ↳ QDPAfsSolverProof
QDP
                    ↳ PisEmptyProof
              ↳ QDP
              ↳ QDP
              ↳ QDP

Q DP problem:
P is empty.
The TRS R consists of the following rules:

from1(X) -> cons2(X, from1(s1(X)))
2ndspos2(0, Z) -> rnil
2ndspos2(s1(N), cons2(X, Z)) -> 2ndspos2(s1(N), cons22(X, Z))
2ndspos2(s1(N), cons22(X, cons2(Y, Z))) -> rcons2(posrecip1(Y), 2ndsneg2(N, Z))
2ndsneg2(0, Z) -> rnil
2ndsneg2(s1(N), cons2(X, Z)) -> 2ndsneg2(s1(N), cons22(X, Z))
2ndsneg2(s1(N), cons22(X, cons2(Y, Z))) -> rcons2(negrecip1(Y), 2ndspos2(N, Z))
pi1(X) -> 2ndspos2(X, from1(0))
plus2(0, Y) -> Y
plus2(s1(X), Y) -> s1(plus2(X, Y))
times2(0, Y) -> 0
times2(s1(X), Y) -> plus2(Y, times2(X, Y))
square1(X) -> times2(X, X)

The set Q consists of the following terms:

from1(x0)
2ndspos2(0, x0)
2ndspos2(s1(x0), cons2(x1, x2))
2ndspos2(s1(x0), cons22(x1, cons2(x2, x3)))
2ndsneg2(0, x0)
2ndsneg2(s1(x0), cons2(x1, x2))
2ndsneg2(s1(x0), cons22(x1, cons2(x2, x3)))
pi1(x0)
plus2(0, x0)
plus2(s1(x0), x1)
times2(0, x0)
times2(s1(x0), x1)
square1(x0)

We have to consider all minimal (P,Q,R)-chains.
The TRS P is empty. Hence, there is no (P,Q,R) chain.

↳ QTRS
  ↳ Non-Overlap Check
    ↳ QTRS
      ↳ DependencyPairsProof
        ↳ QDP
          ↳ DependencyGraphProof
            ↳ AND
              ↳ QDP
QDP
                ↳ QDPAfsSolverProof
              ↳ QDP
              ↳ QDP

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

TIMES2(s1(X), Y) -> TIMES2(X, Y)

The TRS R consists of the following rules:

from1(X) -> cons2(X, from1(s1(X)))
2ndspos2(0, Z) -> rnil
2ndspos2(s1(N), cons2(X, Z)) -> 2ndspos2(s1(N), cons22(X, Z))
2ndspos2(s1(N), cons22(X, cons2(Y, Z))) -> rcons2(posrecip1(Y), 2ndsneg2(N, Z))
2ndsneg2(0, Z) -> rnil
2ndsneg2(s1(N), cons2(X, Z)) -> 2ndsneg2(s1(N), cons22(X, Z))
2ndsneg2(s1(N), cons22(X, cons2(Y, Z))) -> rcons2(negrecip1(Y), 2ndspos2(N, Z))
pi1(X) -> 2ndspos2(X, from1(0))
plus2(0, Y) -> Y
plus2(s1(X), Y) -> s1(plus2(X, Y))
times2(0, Y) -> 0
times2(s1(X), Y) -> plus2(Y, times2(X, Y))
square1(X) -> times2(X, X)

The set Q consists of the following terms:

from1(x0)
2ndspos2(0, x0)
2ndspos2(s1(x0), cons2(x1, x2))
2ndspos2(s1(x0), cons22(x1, cons2(x2, x3)))
2ndsneg2(0, x0)
2ndsneg2(s1(x0), cons2(x1, x2))
2ndsneg2(s1(x0), cons22(x1, cons2(x2, x3)))
pi1(x0)
plus2(0, x0)
plus2(s1(x0), x1)
times2(0, x0)
times2(s1(x0), x1)
square1(x0)

We have to consider all minimal (P,Q,R)-chains.
By using an argument filtering and a montonic ordering, at least one Dependency Pair of this SCC can be strictly oriented.

TIMES2(s1(X), Y) -> TIMES2(X, Y)
Used argument filtering: TIMES2(x1, x2)  =  x1
s1(x1)  =  s1(x1)
Used ordering: Quasi Precedence: trivial


↳ QTRS
  ↳ Non-Overlap Check
    ↳ QTRS
      ↳ DependencyPairsProof
        ↳ QDP
          ↳ DependencyGraphProof
            ↳ AND
              ↳ QDP
              ↳ QDP
                ↳ QDPAfsSolverProof
QDP
                    ↳ PisEmptyProof
              ↳ QDP
              ↳ QDP

Q DP problem:
P is empty.
The TRS R consists of the following rules:

from1(X) -> cons2(X, from1(s1(X)))
2ndspos2(0, Z) -> rnil
2ndspos2(s1(N), cons2(X, Z)) -> 2ndspos2(s1(N), cons22(X, Z))
2ndspos2(s1(N), cons22(X, cons2(Y, Z))) -> rcons2(posrecip1(Y), 2ndsneg2(N, Z))
2ndsneg2(0, Z) -> rnil
2ndsneg2(s1(N), cons2(X, Z)) -> 2ndsneg2(s1(N), cons22(X, Z))
2ndsneg2(s1(N), cons22(X, cons2(Y, Z))) -> rcons2(negrecip1(Y), 2ndspos2(N, Z))
pi1(X) -> 2ndspos2(X, from1(0))
plus2(0, Y) -> Y
plus2(s1(X), Y) -> s1(plus2(X, Y))
times2(0, Y) -> 0
times2(s1(X), Y) -> plus2(Y, times2(X, Y))
square1(X) -> times2(X, X)

The set Q consists of the following terms:

from1(x0)
2ndspos2(0, x0)
2ndspos2(s1(x0), cons2(x1, x2))
2ndspos2(s1(x0), cons22(x1, cons2(x2, x3)))
2ndsneg2(0, x0)
2ndsneg2(s1(x0), cons2(x1, x2))
2ndsneg2(s1(x0), cons22(x1, cons2(x2, x3)))
pi1(x0)
plus2(0, x0)
plus2(s1(x0), x1)
times2(0, x0)
times2(s1(x0), x1)
square1(x0)

We have to consider all minimal (P,Q,R)-chains.
The TRS P is empty. Hence, there is no (P,Q,R) chain.

↳ QTRS
  ↳ Non-Overlap Check
    ↳ QTRS
      ↳ DependencyPairsProof
        ↳ QDP
          ↳ DependencyGraphProof
            ↳ AND
              ↳ QDP
              ↳ QDP
QDP
                ↳ QDPAfsSolverProof
              ↳ QDP

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

2NDSNEG2(s1(N), cons2(X, Z)) -> 2NDSNEG2(s1(N), cons22(X, Z))
2NDSNEG2(s1(N), cons22(X, cons2(Y, Z))) -> 2NDSPOS2(N, Z)
2NDSPOS2(s1(N), cons2(X, Z)) -> 2NDSPOS2(s1(N), cons22(X, Z))
2NDSPOS2(s1(N), cons22(X, cons2(Y, Z))) -> 2NDSNEG2(N, Z)

The TRS R consists of the following rules:

from1(X) -> cons2(X, from1(s1(X)))
2ndspos2(0, Z) -> rnil
2ndspos2(s1(N), cons2(X, Z)) -> 2ndspos2(s1(N), cons22(X, Z))
2ndspos2(s1(N), cons22(X, cons2(Y, Z))) -> rcons2(posrecip1(Y), 2ndsneg2(N, Z))
2ndsneg2(0, Z) -> rnil
2ndsneg2(s1(N), cons2(X, Z)) -> 2ndsneg2(s1(N), cons22(X, Z))
2ndsneg2(s1(N), cons22(X, cons2(Y, Z))) -> rcons2(negrecip1(Y), 2ndspos2(N, Z))
pi1(X) -> 2ndspos2(X, from1(0))
plus2(0, Y) -> Y
plus2(s1(X), Y) -> s1(plus2(X, Y))
times2(0, Y) -> 0
times2(s1(X), Y) -> plus2(Y, times2(X, Y))
square1(X) -> times2(X, X)

The set Q consists of the following terms:

from1(x0)
2ndspos2(0, x0)
2ndspos2(s1(x0), cons2(x1, x2))
2ndspos2(s1(x0), cons22(x1, cons2(x2, x3)))
2ndsneg2(0, x0)
2ndsneg2(s1(x0), cons2(x1, x2))
2ndsneg2(s1(x0), cons22(x1, cons2(x2, x3)))
pi1(x0)
plus2(0, x0)
plus2(s1(x0), x1)
times2(0, x0)
times2(s1(x0), x1)
square1(x0)

We have to consider all minimal (P,Q,R)-chains.
By using an argument filtering and a montonic ordering, at least one Dependency Pair of this SCC can be strictly oriented.

2NDSNEG2(s1(N), cons2(X, Z)) -> 2NDSNEG2(s1(N), cons22(X, Z))
2NDSNEG2(s1(N), cons22(X, cons2(Y, Z))) -> 2NDSPOS2(N, Z)
2NDSPOS2(s1(N), cons2(X, Z)) -> 2NDSPOS2(s1(N), cons22(X, Z))
2NDSPOS2(s1(N), cons22(X, cons2(Y, Z))) -> 2NDSNEG2(N, Z)
Used argument filtering: 2NDSNEG2(x1, x2)  =  x2
cons2(x1, x2)  =  cons1(x2)
cons22(x1, x2)  =  x2
2NDSPOS2(x1, x2)  =  x2
Used ordering: Quasi Precedence: trivial


↳ QTRS
  ↳ Non-Overlap Check
    ↳ QTRS
      ↳ DependencyPairsProof
        ↳ QDP
          ↳ DependencyGraphProof
            ↳ AND
              ↳ QDP
              ↳ QDP
              ↳ QDP
                ↳ QDPAfsSolverProof
QDP
                    ↳ PisEmptyProof
              ↳ QDP

Q DP problem:
P is empty.
The TRS R consists of the following rules:

from1(X) -> cons2(X, from1(s1(X)))
2ndspos2(0, Z) -> rnil
2ndspos2(s1(N), cons2(X, Z)) -> 2ndspos2(s1(N), cons22(X, Z))
2ndspos2(s1(N), cons22(X, cons2(Y, Z))) -> rcons2(posrecip1(Y), 2ndsneg2(N, Z))
2ndsneg2(0, Z) -> rnil
2ndsneg2(s1(N), cons2(X, Z)) -> 2ndsneg2(s1(N), cons22(X, Z))
2ndsneg2(s1(N), cons22(X, cons2(Y, Z))) -> rcons2(negrecip1(Y), 2ndspos2(N, Z))
pi1(X) -> 2ndspos2(X, from1(0))
plus2(0, Y) -> Y
plus2(s1(X), Y) -> s1(plus2(X, Y))
times2(0, Y) -> 0
times2(s1(X), Y) -> plus2(Y, times2(X, Y))
square1(X) -> times2(X, X)

The set Q consists of the following terms:

from1(x0)
2ndspos2(0, x0)
2ndspos2(s1(x0), cons2(x1, x2))
2ndspos2(s1(x0), cons22(x1, cons2(x2, x3)))
2ndsneg2(0, x0)
2ndsneg2(s1(x0), cons2(x1, x2))
2ndsneg2(s1(x0), cons22(x1, cons2(x2, x3)))
pi1(x0)
plus2(0, x0)
plus2(s1(x0), x1)
times2(0, x0)
times2(s1(x0), x1)
square1(x0)

We have to consider all minimal (P,Q,R)-chains.
The TRS P is empty. Hence, there is no (P,Q,R) chain.

↳ QTRS
  ↳ Non-Overlap Check
    ↳ QTRS
      ↳ DependencyPairsProof
        ↳ QDP
          ↳ DependencyGraphProof
            ↳ AND
              ↳ QDP
              ↳ QDP
              ↳ QDP
QDP

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

FROM1(X) -> FROM1(s1(X))

The TRS R consists of the following rules:

from1(X) -> cons2(X, from1(s1(X)))
2ndspos2(0, Z) -> rnil
2ndspos2(s1(N), cons2(X, Z)) -> 2ndspos2(s1(N), cons22(X, Z))
2ndspos2(s1(N), cons22(X, cons2(Y, Z))) -> rcons2(posrecip1(Y), 2ndsneg2(N, Z))
2ndsneg2(0, Z) -> rnil
2ndsneg2(s1(N), cons2(X, Z)) -> 2ndsneg2(s1(N), cons22(X, Z))
2ndsneg2(s1(N), cons22(X, cons2(Y, Z))) -> rcons2(negrecip1(Y), 2ndspos2(N, Z))
pi1(X) -> 2ndspos2(X, from1(0))
plus2(0, Y) -> Y
plus2(s1(X), Y) -> s1(plus2(X, Y))
times2(0, Y) -> 0
times2(s1(X), Y) -> plus2(Y, times2(X, Y))
square1(X) -> times2(X, X)

The set Q consists of the following terms:

from1(x0)
2ndspos2(0, x0)
2ndspos2(s1(x0), cons2(x1, x2))
2ndspos2(s1(x0), cons22(x1, cons2(x2, x3)))
2ndsneg2(0, x0)
2ndsneg2(s1(x0), cons2(x1, x2))
2ndsneg2(s1(x0), cons22(x1, cons2(x2, x3)))
pi1(x0)
plus2(0, x0)
plus2(s1(x0), x1)
times2(0, x0)
times2(s1(x0), x1)
square1(x0)

We have to consider all minimal (P,Q,R)-chains.