ceta_eq: termination proof not accepted
1: error below switch to dependency pairs
1.1: error below the dependency graph processor
 1.1.1: error below the reduction pair processor
  1.1.1.1: error below the reduction pair processor
   1.1.1.1.1: error below the reduction pair processor
    1.1.1.1.1.1: error below the reduction pair processor
     1.1.1.1.1.1.1: error below the reduction pair processor
      1.1.1.1.1.1.1.1: error below the reduction pair processor
       1.1.1.1.1.1.1.1.1: error when applying the reduction pair processor with usable rules to remove from the DP problem
        pairs:
        
        mark#(U31(X)) -> mark#(X)
        mark#(U61(X)) -> mark#(X)
        mark#(U72(X)) -> mark#(X)
        rules:
        
        a__U11(tt) -> tt
        a__U11(X) -> U11(X)
        a__U21(tt, V2) -> a__U22(a__isList(V2))
        a__U21(X1, X2) -> U21(X1, X2)
        a__U22(tt) -> tt
        a__U22(X) -> U22(X)
        a__U31(tt) -> tt
        a__U31(X) -> U31(X)
        a__U41(tt, V2) -> a__U42(a__isNeList(V2))
        a__U41(X1, X2) -> U41(X1, X2)
        a__U42(tt) -> tt
        a__U42(X) -> U42(X)
        a__U51(tt, V2) -> a__U52(a__isList(V2))
        a__U51(X1, X2) -> U51(X1, X2)
        a__U52(tt) -> tt
        a__U52(X) -> U52(X)
        a__U61(tt) -> tt
        a__U61(X) -> U61(X)
        a__U71(tt, P) -> a__U72(a__isPal(P))
        a__U71(X1, X2) -> U71(X1, X2)
        a__U72(tt) -> tt
        a__U72(X) -> U72(X)
        a__U81(tt) -> tt
        a__U81(X) -> U81(X)
        a____(__(X, Y), Z) -> a____(mark(X), a____(mark(Y), mark(Z)))
        a____(X, nil) -> mark(X)
        a____(nil, X) -> mark(X)
        a____(X1, X2) -> __(X1, X2)
        a__isList(V) -> a__U11(a__isNeList(V))
        a__isList(nil) -> tt
        a__isList(__(V1, V2)) -> a__U21(a__isList(V1), V2)
        a__isList(X) -> isList(X)
        a__isNeList(V) -> a__U31(a__isQid(V))
        a__isNeList(__(V1, V2)) -> a__U41(a__isList(V1), V2)
        a__isNeList(__(V1, V2)) -> a__U51(a__isNeList(V1), V2)
        a__isNeList(X) -> isNeList(X)
        a__isNePal(V) -> a__U61(a__isQid(V))
        a__isNePal(__(I, __(P, I))) -> a__U71(a__isQid(I), P)
        a__isNePal(X) -> isNePal(X)
        a__isPal(V) -> a__U81(a__isNePal(V))
        a__isPal(nil) -> tt
        a__isPal(X) -> isPal(X)
        a__isQid(a) -> tt
        a__isQid(e) -> tt
        a__isQid(i) -> tt
        a__isQid(o) -> tt
        a__isQid(u) -> tt
        a__isQid(X) -> isQid(X)
        mark(__(X1, X2)) -> a____(mark(X1), mark(X2))
        mark(U11(X)) -> a__U11(mark(X))
        mark(U21(X1, X2)) -> a__U21(mark(X1), X2)
        mark(U22(X)) -> a__U22(mark(X))
        mark(isList(X)) -> a__isList(X)
        mark(U31(X)) -> a__U31(mark(X))
        mark(U41(X1, X2)) -> a__U41(mark(X1), X2)
        mark(U42(X)) -> a__U42(mark(X))
        mark(isNeList(X)) -> a__isNeList(X)
        mark(U51(X1, X2)) -> a__U51(mark(X1), X2)
        mark(U52(X)) -> a__U52(mark(X))
        mark(U61(X)) -> a__U61(mark(X))
        mark(U71(X1, X2)) -> a__U71(mark(X1), X2)
        mark(U72(X)) -> a__U72(mark(X))
        mark(isPal(X)) -> a__isPal(X)
        mark(U81(X)) -> a__U81(mark(X))
        mark(isQid(X)) -> a__isQid(X)
        mark(isNePal(X)) -> a__isNePal(X)
        mark(nil) -> nil
        mark(tt) -> tt
        mark(a) -> a
        mark(e) -> e
        mark(i) -> i
        mark(o) -> o
        mark(u) -> u
        
         the pairs 
        mark#(U61(X)) -> mark#(X)
        
        could not apply the generic root reduction pair processor with the following
        SCNP-version with mu = MS and the level mapping defined by 
        pi(mark#) = [(epsilon,0),(1,0)]
        Argument Filter: 
        pi(mark#/1) = []
        pi(U31/1) = 1
        pi(U61/1) = [1]
        pi(U72/1) = 1
        
        RPO with the following precedence
        precedence(mark#[1]) = 0
        precedence(U61[1]) = 1
        
        precedence(_) = 0
        and the following status
        status(mark#[1]) = lex
        status(U61[1]) = lex
        
        status(_) = lex
        
        problem when orienting DPs
        cannot orient pair mark#(U31(X)) -> mark#(X) weakly:
        [(mark#(U31(X)),0),(U31(X),0)] >=mu [(mark#(X),0),(X,0)] could not be ensured