Term Rewriting System R: [x, y, z] .(1, x) -> x .(x, 1) -> x .(i(x), x) -> 1 .(x, i(x)) -> 1 .(i(y), .(y, z)) -> z .(y, .(i(y), z)) -> z .(.(x, y), z) -> .(x, .(y, z)) i(1) -> 1 i(i(x)) -> x i(.(x, y)) -> .(i(y), i(x)) Termination of R to be shown. Removing the following rules from R which fullfill a polynomial ordering: .(1, x) -> x .(x, 1) -> x .(i(x), x) -> 1 .(x, i(x)) -> 1 .(i(y), .(y, z)) -> z .(y, .(i(y), z)) -> z where the Polynomial interpretation: POL(1) = 0 POL(i(x_1)) = x_1 POL(.(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: i(1) -> 1 where the Polynomial interpretation: POL(1) = 1 POL(i(x_1)) = 2*x_1 POL(.(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: i(i(x)) -> x where the Polynomial interpretation: POL(i(x_1)) = 1 + 2*x_1 POL(.(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: i(.(x, y)) -> .(i(y), i(x)) where the Polynomial interpretation: POL(i(x_1)) = 2*x_1 POL(.(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: .(.(x, y), z) -> .(x, .(y, z)) where the Polynomial interpretation: POL(.(x_1, x_2)) = 1 + 2*x_1 + x_2 was used. All Rules of R can be deleted. Termination of R successfully shown. Duration: 0.495 seconds.