Problem: app (abs (\x. T x)) S -> T S app (abs (\y. abs (\x. M y x))) S -> abs (\x. app (abs (\y. M y x)) S) app (app (abs (\x. T x)) S) U -> app (abs (\x. app (T x) U)) S Proof: Higher-Order Church Rosser Processor: app (abs (\x. T x)) S -> T S app (abs (\y. abs (\x. M y x))) S -> abs (\x. app (abs (\y. M y x)) S) app (app (abs (\x. T x)) S) U -> app (abs (\x. app (T x) U)) S critical peaks: 4 abs (\290. 291 292 290) <-[]-> abs (\x. app (abs (\y. 291 y x)) 292) app (309 310) U <-[0,1]-> app (abs (\x. app (309 x) U)) 310 abs (\x. app (abs (\y. 319 y x)) 320) <-[]-> abs (\x. 319 320 x) app (abs (\x. app (abs (\y. 343 y x)) 344)) U <-[0,1]-> app (abs (\x. app (abs (\345. 343 x 345)) U)) 344 Redundant Rules Transformation for Pattern Rewrite Systems: app (abs (\x. T x)) S -> T S Higher-Order Church Rosser Processor: app (abs (\x. T x)) S -> T S critical peaks: 0 Higher-Order Closedness Processor: all critical pairs are trivial Qed