The rewrite relation of the following TRS is considered.
U11(tt) | → | N | (1) |
U21(tt) | → | s(plus(N,M)) | (2) |
and(tt) | → | X | (3) |
isNat | → | tt | (4) |
isNat | → | and(isNat) | (5) |
isNat | → | isNat | (6) |
plus(N,0) | → | U11(isNat) | (7) |
plus(N,s(M)) | → | U21(and(isNat)) | (8) |
The TRS violates one of the two variable conditions. Thus, it is not terminating.