MAYBE

The TRS could not be proven terminating. The proof attempt took 299 ms.

The following DP Processors were used


Problem 1 was processed with processor DependencyGraph (0ms).
 | – Problem 2 remains open; application of the following processors failed [SubtermCriterion (1ms), DependencyGraph (1ms), PolynomialLinearRange4iUR (61ms), DependencyGraph (1ms), PolynomialLinearRange8NegiUR (67ms), DependencyGraph (1ms), ReductionPairSAT (18ms), DependencyGraph (3ms), SizeChangePrinciple (4ms)].
 | – Problem 3 was processed with processor SubtermCriterion (0ms).
 | – Problem 4 was processed with processor SubtermCriterion (0ms).

The following open problems remain:



Open Dependency Pair Problem 2

Dependency Pairs

from#(X)from#(s(X))

Rewrite Rules

from(X)cons(X, from(s(X)))head(cons(X, XS))X
2nd(cons(X, XS))head(XS)take(0, XS)nil
take(s(N), cons(X, XS))cons(X, take(N, XS))sel(0, cons(X, XS))X
sel(s(N), cons(X, XS))sel(N, XS)

Original Signature

Termination of terms over the following signature is verified: 2nd, 0, s, take, from, head, sel, nil, cons


Problem 1: DependencyGraph



Dependency Pair Problem

Dependency Pairs

2nd#(cons(X, XS))head#(XS)take#(s(N), cons(X, XS))take#(N, XS)
from#(X)from#(s(X))sel#(s(N), cons(X, XS))sel#(N, XS)

Rewrite Rules

from(X)cons(X, from(s(X)))head(cons(X, XS))X
2nd(cons(X, XS))head(XS)take(0, XS)nil
take(s(N), cons(X, XS))cons(X, take(N, XS))sel(0, cons(X, XS))X
sel(s(N), cons(X, XS))sel(N, XS)

Original Signature

Termination of terms over the following signature is verified: 2nd, 0, s, take, from, head, sel, cons, nil

Strategy


The following SCCs where found

take#(s(N), cons(X, XS)) → take#(N, XS)

from#(X) → from#(s(X))

sel#(s(N), cons(X, XS)) → sel#(N, XS)

Problem 3: SubtermCriterion



Dependency Pair Problem

Dependency Pairs

take#(s(N), cons(X, XS))take#(N, XS)

Rewrite Rules

from(X)cons(X, from(s(X)))head(cons(X, XS))X
2nd(cons(X, XS))head(XS)take(0, XS)nil
take(s(N), cons(X, XS))cons(X, take(N, XS))sel(0, cons(X, XS))X
sel(s(N), cons(X, XS))sel(N, XS)

Original Signature

Termination of terms over the following signature is verified: 2nd, 0, s, take, from, head, sel, cons, nil

Strategy


Projection

The following projection was used:

Thus, the following dependency pairs are removed:

take#(s(N), cons(X, XS))take#(N, XS)

Problem 4: SubtermCriterion



Dependency Pair Problem

Dependency Pairs

sel#(s(N), cons(X, XS))sel#(N, XS)

Rewrite Rules

from(X)cons(X, from(s(X)))head(cons(X, XS))X
2nd(cons(X, XS))head(XS)take(0, XS)nil
take(s(N), cons(X, XS))cons(X, take(N, XS))sel(0, cons(X, XS))X
sel(s(N), cons(X, XS))sel(N, XS)

Original Signature

Termination of terms over the following signature is verified: 2nd, 0, s, take, from, head, sel, cons, nil

Strategy


Projection

The following projection was used:

Thus, the following dependency pairs are removed:

sel#(s(N), cons(X, XS))sel#(N, XS)