t; SUBX(X; UP(X)))
t:Term. f(t) 
Term
= y == x = yt,x:Term. (t = x) Propt,r:Term. SUBX(t; r) Term| Some definitions of interest. | |
| f | Def f(t) == SUBX(t; SUBX(X; UP(X))) |
| Thm* t:Term. f(t) Term | |
| repst | Def x = y == x = y |
| Thm* t,x:Term. (t = x) Prop | |
| subx | Def SUBX(t; e) == t[e/X] |
| Thm* t,r:Term. SUBX(t; r) Term |
About:
 |  |  |  |