| 1: | app(app(iterate,f),x) | → app(app(cons,x),app(app(iterate,f),app(f,x))) | |
| 2: | APP(app(iterate,f),x) | → APP(app(cons,x),app(app(iterate,f),app(f,x))) | |
| 3: | APP(app(iterate,f),x) | → APP(cons,x) | |
| 4: | APP(app(iterate,f),x) | → APP(app(iterate,f),app(f,x)) | |
| 5: | APP(app(iterate,f),x) | → APP(f,x) | |