MAYBE (ignored inputs)COMMENT from van Oostrom ( AJSW 2016 ) submitted by: Vincent van Oostrom input TRS: [ g(f(b,?x)) -> g(h(h(f(f(h(k(k(?x,?x),?x)),h(k(k(?x,?x),?x))),h(k(k(?x,?x),?x)))))), f(?x,b) -> h(f(f(?x,?x),?x)), k(?x,b) -> q(?x), q(?x) -> f(?x,b) ] TRS: [ g(f(b,?x)) -> g(h(h(f(f(h(k(k(?x,?x),?x)),h(k(k(?x,?x),?x))),h(k(k(?x,?x),?x)))))), f(?x,b) -> h(f(f(?x,?x),?x)), k(?x,b) -> q(?x), q(?x) -> f(?x,b) ] New rules by rule reversing: [ g(f(b,?x)) -> g(h(h(f(f(h(k(k(?x,?x),?x)),h(k(k(?x,?x),?x))),h(k(k(?x,?x),?x)))))), f(?x,b) -> h(f(f(?x,?x),?x)), k(?x,b) -> q(?x), q(?x) -> q(?x), f(?x,b) -> q(?x) ] problems/554.trs: Failure(unknown UNC) (0 msec.)