n
x else f(i) fi
n,m:
, f:(n
m), x:m. f[n:=x] 
(n+1)ma1,a2:A. f(a1) = f(a2) B 
a1 = a2A,B:Type, f:(AB). Inj(A; B; f) Prop
} == {k:
| i 
k < j }m,n:. {m..n} Type
== {i:| 0 < i } Type| Some definitions of interest. | |
| fappend | Def f[n:=x](i) == if i=n x else f(i) fi |
| Thm* n,m:, f:(nm), x:m. f[n:=x] (n+1)m | |
| inject | Def Inj(A; B; f) == a1,a2:A. f(a1) = f(a2) B a1 = a2 |
| Thm* A,B:Type, f:(AB). Inj(A; B; f) Prop | |
| int_seg | Def {i..j} == {k:| i k < j } |
| Thm* m,n:. {m..n} Type | |
| nat_plus | Def == {i:| 0 < i } |
| Thm* Type |
About:
 |  |  |  |  |  |  |
 |  |  |  |  |  |  |  |