Term Rewriting System R: [x] app(f, app(f, x)) -> app(g, app(f, x)) app(g, app(g, x)) -> app(f, x) Termination of R to be shown. Removing the following rules from R which fullfill a polynomial ordering: app(f, app(f, x)) -> app(g, app(f, x)) where the Polynomial interpretation: POL(g) = 1 POL(f) = 2 POL(app(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: app(g, app(g, x)) -> app(f, x) where the Polynomial interpretation: POL(g) = 1 POL(f) = 0 POL(app(x_1, x_2)) = x_1 + x_2 was used. All Rules of R can be deleted. Termination of R successfully shown. Duration: 0.369 seconds.