Term Rewriting System R: [X, Y, Z, X1, X2] active(2nd(cons(X, cons(Y, Z)))) -> mark(Y) active(from(X)) -> mark(cons(X, from(s(X)))) active(2nd(X)) -> 2nd(active(X)) active(cons(X1, X2)) -> cons(active(X1), X2) active(from(X)) -> from(active(X)) active(s(X)) -> s(active(X)) 2nd(mark(X)) -> mark(2nd(X)) 2nd(ok(X)) -> ok(2nd(X)) cons(mark(X1), X2) -> mark(cons(X1, X2)) cons(ok(X1), ok(X2)) -> ok(cons(X1, X2)) from(mark(X)) -> mark(from(X)) from(ok(X)) -> ok(from(X)) s(mark(X)) -> mark(s(X)) s(ok(X)) -> ok(s(X)) proper(2nd(X)) -> 2nd(proper(X)) proper(cons(X1, X2)) -> cons(proper(X1), proper(X2)) proper(from(X)) -> from(proper(X)) proper(s(X)) -> s(proper(X)) top(mark(X)) -> top(proper(X)) top(ok(X)) -> top(active(X)) Termination of R to be shown. Removing the following rules from R which fullfill a polynomial ordering: active(2nd(cons(X, cons(Y, Z)))) -> mark(Y) active(2nd(X)) -> 2nd(active(X)) cons(ok(X1), ok(X2)) -> ok(cons(X1, X2)) top(ok(X)) -> top(active(X)) where the Polynomial interpretation: POL(active(x_1)) = 2*x_1 POL(proper(x_1)) = x_1 POL(s(x_1)) = x_1 POL(top(x_1)) = 1 + x_1 POL(2nd(x_1)) = 1 + 2*x_1 POL(mark(x_1)) = x_1 POL(from(x_1)) = x_1 POL(ok(x_1)) = 1 + 2*x_1 POL(cons(x_1, x_2)) = x_1 + x_2 was used. Not all Rules of R can be deleted, so we still have to regard a part of R. Removing the following rules from R which fullfill a polynomial ordering: active(from(X)) -> mark(cons(X, from(s(X)))) where the Polynomial interpretation: POL(active(x_1)) = 1 + 2*x_1 POL(proper(x_1)) = x_1 POL(s(x_1)) = x_1 POL(top(x_1)) = 1 + x_1 POL(2nd(x_1)) = x_1 POL(mark(x_1)) = x_1 POL(from(x_1)) = x_1 POL(ok(x_1)) = x_1 POL(cons(x_1, x_2)) = x_1 + x_2 was used. Not all Rules of R can be deleted, so we still have to regard a part of R. Removing the following rules from R which fullfill a polynomial ordering: active(cons(X1, X2)) -> cons(active(X1), X2) where the Polynomial interpretation: POL(active(x_1)) = 2*x_1 POL(proper(x_1)) = x_1 POL(s(x_1)) = x_1 POL(top(x_1)) = 2 + x_1 POL(2nd(x_1)) = x_1 POL(mark(x_1)) = x_1 POL(from(x_1)) = x_1 POL(ok(x_1)) = x_1 POL(cons(x_1, x_2)) = 1 + x_1 + x_2 was used. Not all Rules of R can be deleted, so we still have to regard a part of R. Removing the following rules from R which fullfill a polynomial ordering: active(from(X)) -> from(active(X)) where the Polynomial interpretation: POL(active(x_1)) = 2*x_1 POL(proper(x_1)) = x_1 POL(s(x_1)) = x_1 POL(top(x_1)) = 2 + x_1 POL(2nd(x_1)) = x_1 POL(mark(x_1)) = x_1 POL(from(x_1)) = 1 + x_1 POL(ok(x_1)) = x_1 POL(cons(x_1, x_2)) = x_1 + x_2 was used. Not all Rules of R can be deleted, so we still have to regard a part of R. Removing the following rules from R which fullfill a polynomial ordering: active(s(X)) -> s(active(X)) where the Polynomial interpretation: POL(active(x_1)) = 2*x_1 POL(proper(x_1)) = x_1 POL(s(x_1)) = 1 + x_1 POL(top(x_1)) = 2 + x_1 POL(2nd(x_1)) = x_1 POL(mark(x_1)) = x_1 POL(from(x_1)) = x_1 POL(ok(x_1)) = x_1 POL(cons(x_1, x_2)) = x_1 + x_2 was used. Not all Rules of R can be deleted, so we still have to regard a part of R. Removing the following rules from R which fullfill a polynomial ordering: s(mark(X)) -> mark(s(X)) top(mark(X)) -> top(proper(X)) where the Polynomial interpretation: POL(proper(x_1)) = x_1 POL(s(x_1)) = 2*x_1 POL(top(x_1)) = 2 + x_1 POL(2nd(x_1)) = x_1 POL(mark(x_1)) = 1 + x_1 POL(from(x_1)) = x_1 POL(ok(x_1)) = x_1 POL(cons(x_1, x_2)) = x_1 + x_2 was used. Not all Rules of R can be deleted, so we still have to regard a part of R. Removing the following rules from R which fullfill a polynomial ordering: s(ok(X)) -> ok(s(X)) where the Polynomial interpretation: POL(proper(x_1)) = x_1 POL(s(x_1)) = 2*x_1 POL(2nd(x_1)) = x_1 POL(mark(x_1)) = x_1 POL(from(x_1)) = x_1 POL(ok(x_1)) = 1 + x_1 POL(cons(x_1, x_2)) = x_1 + x_2 was used. Not all Rules of R can be deleted, so we still have to regard a part of R. Removing the following rules from R which fullfill a polynomial ordering: from(mark(X)) -> mark(from(X)) where the Polynomial interpretation: POL(proper(x_1)) = x_1 POL(s(x_1)) = x_1 POL(2nd(x_1)) = x_1 POL(mark(x_1)) = 1 + x_1 POL(from(x_1)) = 2*x_1 POL(ok(x_1)) = x_1 POL(cons(x_1, x_2)) = x_1 + x_2 was used. Not all Rules of R can be deleted, so we still have to regard a part of R. Removing the following rules from R which fullfill a polynomial ordering: from(ok(X)) -> ok(from(X)) where the Polynomial interpretation: POL(proper(x_1)) = x_1 POL(s(x_1)) = x_1 POL(2nd(x_1)) = x_1 POL(mark(x_1)) = x_1 POL(from(x_1)) = 2*x_1 POL(ok(x_1)) = 1 + x_1 POL(cons(x_1, x_2)) = x_1 + x_2 was used. Not all Rules of R can be deleted, so we still have to regard a part of R. Removing the following rules from R which fullfill a polynomial ordering: cons(mark(X1), X2) -> mark(cons(X1, X2)) where the Polynomial interpretation: POL(proper(x_1)) = x_1 POL(s(x_1)) = x_1 POL(2nd(x_1)) = x_1 POL(mark(x_1)) = 1 + x_1 POL(from(x_1)) = x_1 POL(ok(x_1)) = x_1 POL(cons(x_1, x_2)) = 2*x_1 + x_2 was used. Not all Rules of R can be deleted, so we still have to regard a part of R. Removing the following rules from R which fullfill a polynomial ordering: 2nd(mark(X)) -> mark(2nd(X)) where the Polynomial interpretation: POL(proper(x_1)) = x_1 POL(s(x_1)) = x_1 POL(2nd(x_1)) = 2*x_1 POL(mark(x_1)) = 1 + x_1 POL(from(x_1)) = x_1 POL(ok(x_1)) = x_1 POL(cons(x_1, x_2)) = x_1 + x_2 was used. Not all Rules of R can be deleted, so we still have to regard a part of R. Removing the following rules from R which fullfill a polynomial ordering: 2nd(ok(X)) -> ok(2nd(X)) where the Polynomial interpretation: POL(proper(x_1)) = x_1 POL(s(x_1)) = x_1 POL(2nd(x_1)) = 2*x_1 POL(from(x_1)) = x_1 POL(ok(x_1)) = 1 + x_1 POL(cons(x_1, x_2)) = x_1 + x_2 was used. Not all Rules of R can be deleted, so we still have to regard a part of R. Removing the following rules from R which fullfill a polynomial ordering: proper(2nd(X)) -> 2nd(proper(X)) where the Polynomial interpretation: POL(proper(x_1)) = 2*x_1 POL(s(x_1)) = x_1 POL(2nd(x_1)) = 1 + x_1 POL(from(x_1)) = x_1 POL(cons(x_1, x_2)) = x_1 + x_2 was used. Not all Rules of R can be deleted, so we still have to regard a part of R. Removing the following rules from R which fullfill a polynomial ordering: proper(cons(X1, X2)) -> cons(proper(X1), proper(X2)) where the Polynomial interpretation: POL(proper(x_1)) = 2*x_1 POL(s(x_1)) = x_1 POL(from(x_1)) = x_1 POL(cons(x_1, x_2)) = 1 + x_1 + x_2 was used. Not all Rules of R can be deleted, so we still have to regard a part of R. Removing the following rules from R which fullfill a polynomial ordering: proper(from(X)) -> from(proper(X)) where the Polynomial interpretation: POL(proper(x_1)) = 2*x_1 POL(s(x_1)) = x_1 POL(from(x_1)) = 1 + x_1 was used. Not all Rules of R can be deleted, so we still have to regard a part of R. Removing the following rules from R which fullfill a polynomial ordering: proper(s(X)) -> s(proper(X)) where the Polynomial interpretation: POL(proper(x_1)) = 2*x_1 POL(s(x_1)) = 1 + x_1 was used. All Rules of R can be deleted. Termination of R successfully shown. Duration: 0.659 seconds.