| Step |
Hyp |
Ref |
Expression |
| 1 |
|
isfi |
|- ( A e. Fin <-> E. x e. _om A ~~ x ) |
| 2 |
|
relen |
|- Rel ~~ |
| 3 |
2
|
brrelex1i |
|- ( A ~~ x -> A e. _V ) |
| 4 |
|
pssss |
|- ( B C. A -> B C_ A ) |
| 5 |
|
ssdomg |
|- ( A e. _V -> ( B C_ A -> B ~<_ A ) ) |
| 6 |
5
|
imp |
|- ( ( A e. _V /\ B C_ A ) -> B ~<_ A ) |
| 7 |
3 4 6
|
syl2an |
|- ( ( A ~~ x /\ B C. A ) -> B ~<_ A ) |
| 8 |
7
|
adantll |
|- ( ( ( x e. _om /\ A ~~ x ) /\ B C. A ) -> B ~<_ A ) |
| 9 |
|
bren |
|- ( A ~~ x <-> E. f f : A -1-1-onto-> x ) |
| 10 |
|
imass2 |
|- ( B C_ A -> ( f " B ) C_ ( f " A ) ) |
| 11 |
4 10
|
syl |
|- ( B C. A -> ( f " B ) C_ ( f " A ) ) |
| 12 |
11
|
adantl |
|- ( ( f : A -1-1-onto-> x /\ B C. A ) -> ( f " B ) C_ ( f " A ) ) |
| 13 |
|
pssnel |
|- ( B C. A -> E. y ( y e. A /\ -. y e. B ) ) |
| 14 |
|
eldif |
|- ( y e. ( A \ B ) <-> ( y e. A /\ -. y e. B ) ) |
| 15 |
|
f1ofn |
|- ( f : A -1-1-onto-> x -> f Fn A ) |
| 16 |
|
difss |
|- ( A \ B ) C_ A |
| 17 |
|
fnfvima |
|- ( ( f Fn A /\ ( A \ B ) C_ A /\ y e. ( A \ B ) ) -> ( f ` y ) e. ( f " ( A \ B ) ) ) |
| 18 |
17
|
3expia |
|- ( ( f Fn A /\ ( A \ B ) C_ A ) -> ( y e. ( A \ B ) -> ( f ` y ) e. ( f " ( A \ B ) ) ) ) |
| 19 |
15 16 18
|
sylancl |
|- ( f : A -1-1-onto-> x -> ( y e. ( A \ B ) -> ( f ` y ) e. ( f " ( A \ B ) ) ) ) |
| 20 |
|
dff1o3 |
|- ( f : A -1-1-onto-> x <-> ( f : A -onto-> x /\ Fun `' f ) ) |
| 21 |
|
imadif |
|- ( Fun `' f -> ( f " ( A \ B ) ) = ( ( f " A ) \ ( f " B ) ) ) |
| 22 |
20 21
|
simplbiim |
|- ( f : A -1-1-onto-> x -> ( f " ( A \ B ) ) = ( ( f " A ) \ ( f " B ) ) ) |
| 23 |
22
|
eleq2d |
|- ( f : A -1-1-onto-> x -> ( ( f ` y ) e. ( f " ( A \ B ) ) <-> ( f ` y ) e. ( ( f " A ) \ ( f " B ) ) ) ) |
| 24 |
19 23
|
sylibd |
|- ( f : A -1-1-onto-> x -> ( y e. ( A \ B ) -> ( f ` y ) e. ( ( f " A ) \ ( f " B ) ) ) ) |
| 25 |
|
n0i |
|- ( ( f ` y ) e. ( ( f " A ) \ ( f " B ) ) -> -. ( ( f " A ) \ ( f " B ) ) = (/) ) |
| 26 |
24 25
|
syl6 |
|- ( f : A -1-1-onto-> x -> ( y e. ( A \ B ) -> -. ( ( f " A ) \ ( f " B ) ) = (/) ) ) |
| 27 |
14 26
|
biimtrrid |
|- ( f : A -1-1-onto-> x -> ( ( y e. A /\ -. y e. B ) -> -. ( ( f " A ) \ ( f " B ) ) = (/) ) ) |
| 28 |
27
|
exlimdv |
|- ( f : A -1-1-onto-> x -> ( E. y ( y e. A /\ -. y e. B ) -> -. ( ( f " A ) \ ( f " B ) ) = (/) ) ) |
| 29 |
28
|
imp |
|- ( ( f : A -1-1-onto-> x /\ E. y ( y e. A /\ -. y e. B ) ) -> -. ( ( f " A ) \ ( f " B ) ) = (/) ) |
| 30 |
13 29
|
sylan2 |
|- ( ( f : A -1-1-onto-> x /\ B C. A ) -> -. ( ( f " A ) \ ( f " B ) ) = (/) ) |
| 31 |
|
ssdif0 |
|- ( ( f " A ) C_ ( f " B ) <-> ( ( f " A ) \ ( f " B ) ) = (/) ) |
| 32 |
30 31
|
sylnibr |
|- ( ( f : A -1-1-onto-> x /\ B C. A ) -> -. ( f " A ) C_ ( f " B ) ) |
| 33 |
|
dfpss3 |
|- ( ( f " B ) C. ( f " A ) <-> ( ( f " B ) C_ ( f " A ) /\ -. ( f " A ) C_ ( f " B ) ) ) |
| 34 |
12 32 33
|
sylanbrc |
|- ( ( f : A -1-1-onto-> x /\ B C. A ) -> ( f " B ) C. ( f " A ) ) |
| 35 |
|
imadmrn |
|- ( f " dom f ) = ran f |
| 36 |
|
f1odm |
|- ( f : A -1-1-onto-> x -> dom f = A ) |
| 37 |
36
|
imaeq2d |
|- ( f : A -1-1-onto-> x -> ( f " dom f ) = ( f " A ) ) |
| 38 |
|
f1ofo |
|- ( f : A -1-1-onto-> x -> f : A -onto-> x ) |
| 39 |
|
forn |
|- ( f : A -onto-> x -> ran f = x ) |
| 40 |
38 39
|
syl |
|- ( f : A -1-1-onto-> x -> ran f = x ) |
| 41 |
35 37 40
|
3eqtr3a |
|- ( f : A -1-1-onto-> x -> ( f " A ) = x ) |
| 42 |
41
|
psseq2d |
|- ( f : A -1-1-onto-> x -> ( ( f " B ) C. ( f " A ) <-> ( f " B ) C. x ) ) |
| 43 |
42
|
adantr |
|- ( ( f : A -1-1-onto-> x /\ B C. A ) -> ( ( f " B ) C. ( f " A ) <-> ( f " B ) C. x ) ) |
| 44 |
34 43
|
mpbid |
|- ( ( f : A -1-1-onto-> x /\ B C. A ) -> ( f " B ) C. x ) |
| 45 |
|
php |
|- ( ( x e. _om /\ ( f " B ) C. x ) -> -. x ~~ ( f " B ) ) |
| 46 |
44 45
|
sylan2 |
|- ( ( x e. _om /\ ( f : A -1-1-onto-> x /\ B C. A ) ) -> -. x ~~ ( f " B ) ) |
| 47 |
|
f1of1 |
|- ( f : A -1-1-onto-> x -> f : A -1-1-> x ) |
| 48 |
|
f1ores |
|- ( ( f : A -1-1-> x /\ B C_ A ) -> ( f |` B ) : B -1-1-onto-> ( f " B ) ) |
| 49 |
47 4 48
|
syl2an |
|- ( ( f : A -1-1-onto-> x /\ B C. A ) -> ( f |` B ) : B -1-1-onto-> ( f " B ) ) |
| 50 |
|
vex |
|- f e. _V |
| 51 |
50
|
resex |
|- ( f |` B ) e. _V |
| 52 |
|
f1oeq1 |
|- ( y = ( f |` B ) -> ( y : B -1-1-onto-> ( f " B ) <-> ( f |` B ) : B -1-1-onto-> ( f " B ) ) ) |
| 53 |
51 52
|
spcev |
|- ( ( f |` B ) : B -1-1-onto-> ( f " B ) -> E. y y : B -1-1-onto-> ( f " B ) ) |
| 54 |
|
bren |
|- ( B ~~ ( f " B ) <-> E. y y : B -1-1-onto-> ( f " B ) ) |
| 55 |
53 54
|
sylibr |
|- ( ( f |` B ) : B -1-1-onto-> ( f " B ) -> B ~~ ( f " B ) ) |
| 56 |
49 55
|
syl |
|- ( ( f : A -1-1-onto-> x /\ B C. A ) -> B ~~ ( f " B ) ) |
| 57 |
|
entr |
|- ( ( x ~~ B /\ B ~~ ( f " B ) ) -> x ~~ ( f " B ) ) |
| 58 |
57
|
expcom |
|- ( B ~~ ( f " B ) -> ( x ~~ B -> x ~~ ( f " B ) ) ) |
| 59 |
56 58
|
syl |
|- ( ( f : A -1-1-onto-> x /\ B C. A ) -> ( x ~~ B -> x ~~ ( f " B ) ) ) |
| 60 |
59
|
adantl |
|- ( ( x e. _om /\ ( f : A -1-1-onto-> x /\ B C. A ) ) -> ( x ~~ B -> x ~~ ( f " B ) ) ) |
| 61 |
46 60
|
mtod |
|- ( ( x e. _om /\ ( f : A -1-1-onto-> x /\ B C. A ) ) -> -. x ~~ B ) |
| 62 |
61
|
exp32 |
|- ( x e. _om -> ( f : A -1-1-onto-> x -> ( B C. A -> -. x ~~ B ) ) ) |
| 63 |
62
|
exlimdv |
|- ( x e. _om -> ( E. f f : A -1-1-onto-> x -> ( B C. A -> -. x ~~ B ) ) ) |
| 64 |
9 63
|
biimtrid |
|- ( x e. _om -> ( A ~~ x -> ( B C. A -> -. x ~~ B ) ) ) |
| 65 |
64
|
imp31 |
|- ( ( ( x e. _om /\ A ~~ x ) /\ B C. A ) -> -. x ~~ B ) |
| 66 |
|
entr |
|- ( ( B ~~ A /\ A ~~ x ) -> B ~~ x ) |
| 67 |
66
|
ex |
|- ( B ~~ A -> ( A ~~ x -> B ~~ x ) ) |
| 68 |
|
ensym |
|- ( B ~~ x -> x ~~ B ) |
| 69 |
67 68
|
syl6com |
|- ( A ~~ x -> ( B ~~ A -> x ~~ B ) ) |
| 70 |
69
|
ad2antlr |
|- ( ( ( x e. _om /\ A ~~ x ) /\ B C. A ) -> ( B ~~ A -> x ~~ B ) ) |
| 71 |
65 70
|
mtod |
|- ( ( ( x e. _om /\ A ~~ x ) /\ B C. A ) -> -. B ~~ A ) |
| 72 |
|
brsdom |
|- ( B ~< A <-> ( B ~<_ A /\ -. B ~~ A ) ) |
| 73 |
8 71 72
|
sylanbrc |
|- ( ( ( x e. _om /\ A ~~ x ) /\ B C. A ) -> B ~< A ) |
| 74 |
73
|
exp31 |
|- ( x e. _om -> ( A ~~ x -> ( B C. A -> B ~< A ) ) ) |
| 75 |
74
|
rexlimiv |
|- ( E. x e. _om A ~~ x -> ( B C. A -> B ~< A ) ) |
| 76 |
1 75
|
sylbi |
|- ( A e. Fin -> ( B C. A -> B ~< A ) ) |
| 77 |
76
|
imp |
|- ( ( A e. Fin /\ B C. A ) -> B ~< A ) |