| Step |
Hyp |
Ref |
Expression |
| 1 |
|
helch |
|- ~H e. CH |
| 2 |
1
|
jctl |
|- ( A C_ ~H -> ( ~H e. CH /\ A C_ ~H ) ) |
| 3 |
|
sseq2 |
|- ( x = ~H -> ( A C_ x <-> A C_ ~H ) ) |
| 4 |
3
|
elrab |
|- ( ~H e. { x e. CH | A C_ x } <-> ( ~H e. CH /\ A C_ ~H ) ) |
| 5 |
2 4
|
sylibr |
|- ( A C_ ~H -> ~H e. { x e. CH | A C_ x } ) |
| 6 |
|
intss1 |
|- ( ~H e. { x e. CH | A C_ x } -> |^| { x e. CH | A C_ x } C_ ~H ) |
| 7 |
5 6
|
syl |
|- ( A C_ ~H -> |^| { x e. CH | A C_ x } C_ ~H ) |
| 8 |
|
ocss |
|- ( |^| { x e. CH | A C_ x } C_ ~H -> ( _|_ ` |^| { x e. CH | A C_ x } ) C_ ~H ) |
| 9 |
7 8
|
syl |
|- ( A C_ ~H -> ( _|_ ` |^| { x e. CH | A C_ x } ) C_ ~H ) |
| 10 |
|
ocss |
|- ( A C_ ~H -> ( _|_ ` A ) C_ ~H ) |
| 11 |
9 10
|
jca |
|- ( A C_ ~H -> ( ( _|_ ` |^| { x e. CH | A C_ x } ) C_ ~H /\ ( _|_ ` A ) C_ ~H ) ) |
| 12 |
|
ssintub |
|- A C_ |^| { x e. CH | A C_ x } |
| 13 |
|
occon |
|- ( ( A C_ ~H /\ |^| { x e. CH | A C_ x } C_ ~H ) -> ( A C_ |^| { x e. CH | A C_ x } -> ( _|_ ` |^| { x e. CH | A C_ x } ) C_ ( _|_ ` A ) ) ) |
| 14 |
7 13
|
mpdan |
|- ( A C_ ~H -> ( A C_ |^| { x e. CH | A C_ x } -> ( _|_ ` |^| { x e. CH | A C_ x } ) C_ ( _|_ ` A ) ) ) |
| 15 |
12 14
|
mpi |
|- ( A C_ ~H -> ( _|_ ` |^| { x e. CH | A C_ x } ) C_ ( _|_ ` A ) ) |
| 16 |
|
occon |
|- ( ( ( _|_ ` |^| { x e. CH | A C_ x } ) C_ ~H /\ ( _|_ ` A ) C_ ~H ) -> ( ( _|_ ` |^| { x e. CH | A C_ x } ) C_ ( _|_ ` A ) -> ( _|_ ` ( _|_ ` A ) ) C_ ( _|_ ` ( _|_ ` |^| { x e. CH | A C_ x } ) ) ) ) |
| 17 |
11 15 16
|
sylc |
|- ( A C_ ~H -> ( _|_ ` ( _|_ ` A ) ) C_ ( _|_ ` ( _|_ ` |^| { x e. CH | A C_ x } ) ) ) |
| 18 |
|
ssrab2 |
|- { x e. CH | A C_ x } C_ CH |
| 19 |
3
|
rspcev |
|- ( ( ~H e. CH /\ A C_ ~H ) -> E. x e. CH A C_ x ) |
| 20 |
1 19
|
mpan |
|- ( A C_ ~H -> E. x e. CH A C_ x ) |
| 21 |
|
rabn0 |
|- ( { x e. CH | A C_ x } =/= (/) <-> E. x e. CH A C_ x ) |
| 22 |
20 21
|
sylibr |
|- ( A C_ ~H -> { x e. CH | A C_ x } =/= (/) ) |
| 23 |
|
chintcl |
|- ( ( { x e. CH | A C_ x } C_ CH /\ { x e. CH | A C_ x } =/= (/) ) -> |^| { x e. CH | A C_ x } e. CH ) |
| 24 |
18 22 23
|
sylancr |
|- ( A C_ ~H -> |^| { x e. CH | A C_ x } e. CH ) |
| 25 |
|
ococ |
|- ( |^| { x e. CH | A C_ x } e. CH -> ( _|_ ` ( _|_ ` |^| { x e. CH | A C_ x } ) ) = |^| { x e. CH | A C_ x } ) |
| 26 |
24 25
|
syl |
|- ( A C_ ~H -> ( _|_ ` ( _|_ ` |^| { x e. CH | A C_ x } ) ) = |^| { x e. CH | A C_ x } ) |
| 27 |
17 26
|
sseqtrd |
|- ( A C_ ~H -> ( _|_ ` ( _|_ ` A ) ) C_ |^| { x e. CH | A C_ x } ) |
| 28 |
|
occl |
|- ( ( _|_ ` A ) C_ ~H -> ( _|_ ` ( _|_ ` A ) ) e. CH ) |
| 29 |
10 28
|
syl |
|- ( A C_ ~H -> ( _|_ ` ( _|_ ` A ) ) e. CH ) |
| 30 |
|
ococss |
|- ( A C_ ~H -> A C_ ( _|_ ` ( _|_ ` A ) ) ) |
| 31 |
|
sseq2 |
|- ( x = ( _|_ ` ( _|_ ` A ) ) -> ( A C_ x <-> A C_ ( _|_ ` ( _|_ ` A ) ) ) ) |
| 32 |
31
|
elrab |
|- ( ( _|_ ` ( _|_ ` A ) ) e. { x e. CH | A C_ x } <-> ( ( _|_ ` ( _|_ ` A ) ) e. CH /\ A C_ ( _|_ ` ( _|_ ` A ) ) ) ) |
| 33 |
29 30 32
|
sylanbrc |
|- ( A C_ ~H -> ( _|_ ` ( _|_ ` A ) ) e. { x e. CH | A C_ x } ) |
| 34 |
|
intss1 |
|- ( ( _|_ ` ( _|_ ` A ) ) e. { x e. CH | A C_ x } -> |^| { x e. CH | A C_ x } C_ ( _|_ ` ( _|_ ` A ) ) ) |
| 35 |
33 34
|
syl |
|- ( A C_ ~H -> |^| { x e. CH | A C_ x } C_ ( _|_ ` ( _|_ ` A ) ) ) |
| 36 |
27 35
|
eqssd |
|- ( A C_ ~H -> ( _|_ ` ( _|_ ` A ) ) = |^| { x e. CH | A C_ x } ) |