YES TPA v.1.0 Result: TRS is terminating Default interpretations for symbols are not printed. For polynomial interpretations and semantic labelling over N\{0,1} defaults are 2 for constants, identity for unary symbols and x+y-2 for binary symbols. For semantic labelling over {0,1} (booleans) defaults are 0 for constants, identity for unary symbols and disjunction for binary symbols. [1] TRS loaded from input file: (1) 2nd(cons(X,n__cons(Y,Z))) -> activate(Y) (2) from(X) -> cons(X,n__from(s(X))) (3) cons(X1,X2) -> n__cons(X1,X2) (4) from(X) -> n__from(X) (5) activate(n__cons(X1,X2)) -> cons(X1,X2) (6) activate(n__from(X)) -> from(X) (7) activate(X) -> X [2] Eliminate dummy symbol , to obtain the following TRS: (1) 2nd(cons(X,n__cons(Y,Z))) -> activate(Y) (2a) from(X) -> cons(X,n__from(#0)) (2b) from(X) -> #1(X) (3) cons(X1,X2) -> n__cons(X1,X2) (4) from(X) -> n__from(X) (5) activate(n__cons(X1,X2)) -> cons(X1,X2) (6) activate(n__from(X)) -> from(X) (7) activate(X) -> X [3] Use following polynomial interpretation: [2nd(x)] = x + 1 rest default Remove rules with left hand side strictly bigger than right hand side: (1) [4] Use following polynomial interpretation: [activate(x)] = x + 1 rest default Remove rules with left hand side strictly bigger than right hand side: (5)-(7) [5] Use following polynomial interpretation: [from(x)] = x + 1 rest default Remove rules with left hand side strictly bigger than right hand side: (2a)-(2b), (4) [6] Use following polynomial interpretation: [cons(x,y)] = x + y + 1 rest default Remove rules with left hand side strictly bigger than right hand side: (3) [7] Since there are no remaining rules, termination is proved! ../tpdb/TRS/TRCSR/Ex1_2_Luc02c_Z.trs, 0., Y Couldn't open file <60>: 60: No such file or directory