Step |
Hyp |
Ref |
Expression |
1 |
|
inf3lem.1 |
|- G = ( y e. _V |-> { w e. x | ( w i^i x ) C_ y } ) |
2 |
|
inf3lem.2 |
|- F = ( rec ( G , (/) ) |` _om ) |
3 |
|
inf3lem.3 |
|- A e. _V |
4 |
|
inf3lem.4 |
|- B e. _V |
5 |
1 2 3 4
|
inf3lem1 |
|- ( A e. _om -> ( F ` A ) C_ ( F ` suc A ) ) |
6 |
5
|
a1i |
|- ( ( x =/= (/) /\ x C_ U. x ) -> ( A e. _om -> ( F ` A ) C_ ( F ` suc A ) ) ) |
7 |
1 2 3 4
|
inf3lem3 |
|- ( ( x =/= (/) /\ x C_ U. x ) -> ( A e. _om -> ( F ` A ) =/= ( F ` suc A ) ) ) |
8 |
6 7
|
jcad |
|- ( ( x =/= (/) /\ x C_ U. x ) -> ( A e. _om -> ( ( F ` A ) C_ ( F ` suc A ) /\ ( F ` A ) =/= ( F ` suc A ) ) ) ) |
9 |
|
df-pss |
|- ( ( F ` A ) C. ( F ` suc A ) <-> ( ( F ` A ) C_ ( F ` suc A ) /\ ( F ` A ) =/= ( F ` suc A ) ) ) |
10 |
8 9
|
syl6ibr |
|- ( ( x =/= (/) /\ x C_ U. x ) -> ( A e. _om -> ( F ` A ) C. ( F ` suc A ) ) ) |