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 dependency graph processor 1.1.1.1.2: error when applying the reduction pair processor to remove from the DP problem pairs: isNatKind#(n__s(V1)) -> isNatKind#(activate(V1)) rules: 0 -> n__0 U11(tt, V1, V2) -> U12(isNatKind(activate(V1)), activate(V1), activate(V2)) U12(tt, V1, V2) -> U13(isNatKind(activate(V2)), activate(V1), activate(V2)) U13(tt, V1, V2) -> U14(isNatKind(activate(V2)), activate(V1), activate(V2)) U14(tt, V1, V2) -> U15(isNat(activate(V1)), activate(V2)) U15(tt, V2) -> U16(isNat(activate(V2))) U16(tt) -> tt U21(tt, V1) -> U22(isNatKind(activate(V1)), activate(V1)) U22(tt, V1) -> U23(isNat(activate(V1))) U23(tt) -> tt U31(tt, V2) -> U32(isNatKind(activate(V2))) U32(tt) -> tt U41(tt) -> tt U51(tt, N) -> U52(isNatKind(activate(N)), activate(N)) U52(tt, N) -> activate(N) U61(tt, M, N) -> U62(isNatKind(activate(M)), activate(M), activate(N)) U62(tt, M, N) -> U63(isNat(activate(N)), activate(M), activate(N)) U63(tt, M, N) -> U64(isNatKind(activate(N)), activate(M), activate(N)) U64(tt, M, N) -> s(plus(activate(N), activate(M))) activate(n__0) -> 0 activate(n__plus(X1, X2)) -> plus(activate(X1), activate(X2)) activate(n__s(X)) -> s(activate(X)) activate(X) -> X isNat(n__0) -> tt isNat(n__plus(V1, V2)) -> U11(isNatKind(activate(V1)), activate(V1), activate(V2)) isNat(n__s(V1)) -> U21(isNatKind(activate(V1)), activate(V1)) isNatKind(n__0) -> tt isNatKind(n__plus(V1, V2)) -> U31(isNatKind(activate(V1)), activate(V2)) isNatKind(n__s(V1)) -> U41(isNatKind(activate(V1))) plus(N, 0) -> U51(isNat(N), N) plus(N, s(M)) -> U61(isNat(M), M, N) plus(X1, X2) -> n__plus(X1, X2) s(X) -> n__s(X) the pairs isNatKind#(n__s(V1)) -> isNatKind#(activate(V1)) could not apply the generic reduction pair processor with the following Argument Filter: pi(isNatKind#/1) = 1 pi(n__s/1) = [1] pi(activate/1) = 1 pi(n__0/0) = [] pi(0/0) = [] pi(U52/2) = [1,2] pi(tt/0) = [] pi(n__plus/2) = [2,1] pi(plus/2) = [2,1] pi(U51/2) = [1,2] pi(isNat/1) = [] pi(isNatKind/1) = [] pi(s/1) = [1] pi(U61/3) = [2,3,1] pi(U11/3) = 1 pi(U21/2) = 1 pi(U31/2) = 1 pi(U41/1) = 1 pi(U62/3) = [2,3,1] pi(U12/3) = 1 pi(U22/2) = 1 pi(U32/1) = 1 pi(U63/3) = [2,3,1] pi(U13/3) = [] pi(U23/1) = 1 pi(U64/3) = [2,3,1] pi(U14/3) = 1 pi(U15/2) = 1 pi(U16/1) = 1 RPO with the following precedence precedence(n__s[1]) = 0 precedence(n__0[0]) = 2 precedence(0[0]) = 2 precedence(U52[2]) = 0 precedence(tt[0]) = 1 precedence(n__plus[2]) = 1 precedence(plus[2]) = 1 precedence(U51[2]) = 0 precedence(isNat[1]) = 1 precedence(isNatKind[1]) = 1 precedence(s[1]) = 0 precedence(U61[3]) = 1 precedence(U62[3]) = 1 precedence(U63[3]) = 1 precedence(U13[3]) = 1 precedence(U64[3]) = 1 precedence(_) = 0 and the following status status(n__s[1]) = mul status(n__0[0]) = mul status(0[0]) = mul status(U52[2]) = mul status(tt[0]) = mul status(n__plus[2]) = lex status(plus[2]) = lex status(U51[2]) = mul status(isNat[1]) = lex status(isNatKind[1]) = lex status(s[1]) = mul status(U61[3]) = lex status(U62[3]) = lex status(U63[3]) = lex status(U13[3]) = lex status(U64[3]) = lex status(_) = lex problem when orienting (usable) rules could not orient U51(tt, N) >= U52(isNatKind(activate(N)), activate(N)) pi( U51(tt, N) ) = U51(tt, N) pi( U52(isNatKind(activate(N)), activate(N)) ) = U52(isNatKind, N) could not orient U51(tt, N) >=RPO U52(isNatKind, N)