Problem: f x x -> a f x (s x) -> b mu (\x. Z x) -> Z (mu (\x. Z x)) Proof: Higher-Order Church Rosser Processor: f x x -> a f x (s x) -> b mu (\x. Z x) -> Z (mu (\x. Z x)) critical peaks: 0 Redundant Rules Transformation for Pattern Rewrite Systems: f x x -> a f x (s x) -> b mu (\x. Z x) -> Z (mu (\x. Z x)) mu (\x. 70 x) -> 70 (70 (mu (\x. 70 x))) f (mu (\x. s x)) (mu (\x. s x)) -> b Higher-Order Church Rosser Processor: f x x -> a f x (s x) -> b mu (\x. Z x) -> Z (mu (\x. Z x)) mu (\x. 70 x) -> 70 (70 (mu (\x. 70 x))) f (mu (\x. s x)) (mu (\x. s x)) -> b critical peaks: 8 a <-[]-> b 105 (mu (\x. 105 x)) <-[]-> 105 (105 (mu (\x. 105 x))) f (s (mu (\x. s x))) (mu (\x. s x)) <-[0,1]-> b f (mu (\x. s x)) (s (mu (\x. s x))) <-[1]-> b 115 (115 (mu (\x. 115 x))) <-[]-> 115 (mu (\x. 115 x)) f (s (s (mu (\x. s x)))) (mu (\x. s x)) <-[0,1]-> b f (mu (\x. s x)) (s (s (mu (\x. s x)))) <-[1]-> b b <-[]-> a Higher-Order Nonconfluence Processor: non-joinable conversion: a *<- a <- . -> b ->* b Qed