Database
ZF (ZERMELO-FRAENKEL) SET THEORY
ZF Set Theory - add the Axiom of Union
Ordinal arithmetic
oeeulem
Next ⟩
oeeui
Metamath Proof Explorer
Ascii
Unicode
Theorem
oeeulem
Description:
Lemma for
oeeu
.
(Contributed by
Mario Carneiro
, 28-Feb-2013)
Ref
Expression
Hypothesis
oeeu.1
⊢
X
=
⋃
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
Assertion
oeeulem
⊢
A
∈
On
∖
2
𝑜
∧
B
∈
On
∖
1
𝑜
→
X
∈
On
∧
A
↑
𝑜
X
⊆
B
∧
B
∈
A
↑
𝑜
suc
X
Proof
Step
Hyp
Ref
Expression
1
oeeu.1
⊢
X
=
⋃
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
2
eldifi
⊢
B
∈
On
∖
1
𝑜
→
B
∈
On
3
2
adantl
⊢
A
∈
On
∖
2
𝑜
∧
B
∈
On
∖
1
𝑜
→
B
∈
On
4
onsuc
⊢
B
∈
On
→
suc
B
∈
On
5
3
4
syl
⊢
A
∈
On
∖
2
𝑜
∧
B
∈
On
∖
1
𝑜
→
suc
B
∈
On
6
oeworde
⊢
A
∈
On
∖
2
𝑜
∧
suc
B
∈
On
→
suc
B
⊆
A
↑
𝑜
suc
B
7
5
6
syldan
⊢
A
∈
On
∖
2
𝑜
∧
B
∈
On
∖
1
𝑜
→
suc
B
⊆
A
↑
𝑜
suc
B
8
sucidg
⊢
B
∈
On
→
B
∈
suc
B
9
3
8
syl
⊢
A
∈
On
∖
2
𝑜
∧
B
∈
On
∖
1
𝑜
→
B
∈
suc
B
10
7
9
sseldd
⊢
A
∈
On
∖
2
𝑜
∧
B
∈
On
∖
1
𝑜
→
B
∈
A
↑
𝑜
suc
B
11
oveq2
⊢
x
=
suc
B
→
A
↑
𝑜
x
=
A
↑
𝑜
suc
B
12
11
eleq2d
⊢
x
=
suc
B
→
B
∈
A
↑
𝑜
x
↔
B
∈
A
↑
𝑜
suc
B
13
12
rspcev
⊢
suc
B
∈
On
∧
B
∈
A
↑
𝑜
suc
B
→
∃
x
∈
On
B
∈
A
↑
𝑜
x
14
5
10
13
syl2anc
⊢
A
∈
On
∖
2
𝑜
∧
B
∈
On
∖
1
𝑜
→
∃
x
∈
On
B
∈
A
↑
𝑜
x
15
onintrab2
⊢
∃
x
∈
On
B
∈
A
↑
𝑜
x
↔
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
∈
On
16
14
15
sylib
⊢
A
∈
On
∖
2
𝑜
∧
B
∈
On
∖
1
𝑜
→
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
∈
On
17
onuni
⊢
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
∈
On
→
⋃
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
∈
On
18
16
17
syl
⊢
A
∈
On
∖
2
𝑜
∧
B
∈
On
∖
1
𝑜
→
⋃
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
∈
On
19
1
18
eqeltrid
⊢
A
∈
On
∖
2
𝑜
∧
B
∈
On
∖
1
𝑜
→
X
∈
On
20
sucidg
⊢
X
∈
On
→
X
∈
suc
X
21
19
20
syl
⊢
A
∈
On
∖
2
𝑜
∧
B
∈
On
∖
1
𝑜
→
X
∈
suc
X
22
suceq
⊢
X
=
⋃
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
→
suc
X
=
suc
⋃
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
23
1
22
ax-mp
⊢
suc
X
=
suc
⋃
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
24
dif1o
⊢
B
∈
On
∖
1
𝑜
↔
B
∈
On
∧
B
≠
∅
25
24
simprbi
⊢
B
∈
On
∖
1
𝑜
→
B
≠
∅
26
25
adantl
⊢
A
∈
On
∖
2
𝑜
∧
B
∈
On
∖
1
𝑜
→
B
≠
∅
27
ssrab2
⊢
x
∈
On
|
B
∈
A
↑
𝑜
x
⊆
On
28
rabn0
⊢
x
∈
On
|
B
∈
A
↑
𝑜
x
≠
∅
↔
∃
x
∈
On
B
∈
A
↑
𝑜
x
29
14
28
sylibr
⊢
A
∈
On
∖
2
𝑜
∧
B
∈
On
∖
1
𝑜
→
x
∈
On
|
B
∈
A
↑
𝑜
x
≠
∅
30
onint
⊢
x
∈
On
|
B
∈
A
↑
𝑜
x
⊆
On
∧
x
∈
On
|
B
∈
A
↑
𝑜
x
≠
∅
→
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
∈
x
∈
On
|
B
∈
A
↑
𝑜
x
31
27
29
30
sylancr
⊢
A
∈
On
∖
2
𝑜
∧
B
∈
On
∖
1
𝑜
→
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
∈
x
∈
On
|
B
∈
A
↑
𝑜
x
32
eleq1
⊢
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
=
∅
→
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
∈
x
∈
On
|
B
∈
A
↑
𝑜
x
↔
∅
∈
x
∈
On
|
B
∈
A
↑
𝑜
x
33
31
32
syl5ibcom
⊢
A
∈
On
∖
2
𝑜
∧
B
∈
On
∖
1
𝑜
→
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
=
∅
→
∅
∈
x
∈
On
|
B
∈
A
↑
𝑜
x
34
oveq2
⊢
x
=
∅
→
A
↑
𝑜
x
=
A
↑
𝑜
∅
35
34
eleq2d
⊢
x
=
∅
→
B
∈
A
↑
𝑜
x
↔
B
∈
A
↑
𝑜
∅
36
35
elrab
⊢
∅
∈
x
∈
On
|
B
∈
A
↑
𝑜
x
↔
∅
∈
On
∧
B
∈
A
↑
𝑜
∅
37
36
simprbi
⊢
∅
∈
x
∈
On
|
B
∈
A
↑
𝑜
x
→
B
∈
A
↑
𝑜
∅
38
eldifi
⊢
A
∈
On
∖
2
𝑜
→
A
∈
On
39
38
adantr
⊢
A
∈
On
∖
2
𝑜
∧
B
∈
On
∖
1
𝑜
→
A
∈
On
40
oe0
⊢
A
∈
On
→
A
↑
𝑜
∅
=
1
𝑜
41
39
40
syl
⊢
A
∈
On
∖
2
𝑜
∧
B
∈
On
∖
1
𝑜
→
A
↑
𝑜
∅
=
1
𝑜
42
41
eleq2d
⊢
A
∈
On
∖
2
𝑜
∧
B
∈
On
∖
1
𝑜
→
B
∈
A
↑
𝑜
∅
↔
B
∈
1
𝑜
43
el1o
⊢
B
∈
1
𝑜
↔
B
=
∅
44
42
43
bitrdi
⊢
A
∈
On
∖
2
𝑜
∧
B
∈
On
∖
1
𝑜
→
B
∈
A
↑
𝑜
∅
↔
B
=
∅
45
37
44
imbitrid
⊢
A
∈
On
∖
2
𝑜
∧
B
∈
On
∖
1
𝑜
→
∅
∈
x
∈
On
|
B
∈
A
↑
𝑜
x
→
B
=
∅
46
33
45
syld
⊢
A
∈
On
∖
2
𝑜
∧
B
∈
On
∖
1
𝑜
→
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
=
∅
→
B
=
∅
47
46
necon3ad
⊢
A
∈
On
∖
2
𝑜
∧
B
∈
On
∖
1
𝑜
→
B
≠
∅
→
¬
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
=
∅
48
26
47
mpd
⊢
A
∈
On
∖
2
𝑜
∧
B
∈
On
∖
1
𝑜
→
¬
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
=
∅
49
limuni
⊢
Lim
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
→
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
=
⋃
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
50
49
1
eqtr4di
⊢
Lim
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
→
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
=
X
51
50
adantl
⊢
A
∈
On
∖
2
𝑜
∧
B
∈
On
∖
1
𝑜
∧
Lim
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
→
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
=
X
52
31
adantr
⊢
A
∈
On
∖
2
𝑜
∧
B
∈
On
∖
1
𝑜
∧
Lim
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
→
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
∈
x
∈
On
|
B
∈
A
↑
𝑜
x
53
51
52
eqeltrrd
⊢
A
∈
On
∖
2
𝑜
∧
B
∈
On
∖
1
𝑜
∧
Lim
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
→
X
∈
x
∈
On
|
B
∈
A
↑
𝑜
x
54
oveq2
⊢
y
=
X
→
A
↑
𝑜
y
=
A
↑
𝑜
X
55
54
eleq2d
⊢
y
=
X
→
B
∈
A
↑
𝑜
y
↔
B
∈
A
↑
𝑜
X
56
oveq2
⊢
x
=
y
→
A
↑
𝑜
x
=
A
↑
𝑜
y
57
56
eleq2d
⊢
x
=
y
→
B
∈
A
↑
𝑜
x
↔
B
∈
A
↑
𝑜
y
58
57
cbvrabv
⊢
x
∈
On
|
B
∈
A
↑
𝑜
x
=
y
∈
On
|
B
∈
A
↑
𝑜
y
59
55
58
elrab2
⊢
X
∈
x
∈
On
|
B
∈
A
↑
𝑜
x
↔
X
∈
On
∧
B
∈
A
↑
𝑜
X
60
59
simprbi
⊢
X
∈
x
∈
On
|
B
∈
A
↑
𝑜
x
→
B
∈
A
↑
𝑜
X
61
53
60
syl
⊢
A
∈
On
∖
2
𝑜
∧
B
∈
On
∖
1
𝑜
∧
Lim
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
→
B
∈
A
↑
𝑜
X
62
38
ad2antrr
⊢
A
∈
On
∖
2
𝑜
∧
B
∈
On
∖
1
𝑜
∧
Lim
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
→
A
∈
On
63
limeq
⊢
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
=
X
→
Lim
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
↔
Lim
X
64
50
63
syl
⊢
Lim
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
→
Lim
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
↔
Lim
X
65
64
ibi
⊢
Lim
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
→
Lim
X
66
19
65
anim12i
⊢
A
∈
On
∖
2
𝑜
∧
B
∈
On
∖
1
𝑜
∧
Lim
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
→
X
∈
On
∧
Lim
X
67
dif20el
⊢
A
∈
On
∖
2
𝑜
→
∅
∈
A
68
67
ad2antrr
⊢
A
∈
On
∖
2
𝑜
∧
B
∈
On
∖
1
𝑜
∧
Lim
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
→
∅
∈
A
69
oelim
⊢
A
∈
On
∧
X
∈
On
∧
Lim
X
∧
∅
∈
A
→
A
↑
𝑜
X
=
⋃
y
∈
X
A
↑
𝑜
y
70
62
66
68
69
syl21anc
⊢
A
∈
On
∖
2
𝑜
∧
B
∈
On
∖
1
𝑜
∧
Lim
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
→
A
↑
𝑜
X
=
⋃
y
∈
X
A
↑
𝑜
y
71
61
70
eleqtrd
⊢
A
∈
On
∖
2
𝑜
∧
B
∈
On
∖
1
𝑜
∧
Lim
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
→
B
∈
⋃
y
∈
X
A
↑
𝑜
y
72
eliun
⊢
B
∈
⋃
y
∈
X
A
↑
𝑜
y
↔
∃
y
∈
X
B
∈
A
↑
𝑜
y
73
71
72
sylib
⊢
A
∈
On
∖
2
𝑜
∧
B
∈
On
∖
1
𝑜
∧
Lim
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
→
∃
y
∈
X
B
∈
A
↑
𝑜
y
74
19
adantr
⊢
A
∈
On
∖
2
𝑜
∧
B
∈
On
∖
1
𝑜
∧
Lim
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
→
X
∈
On
75
onss
⊢
X
∈
On
→
X
⊆
On
76
74
75
syl
⊢
A
∈
On
∖
2
𝑜
∧
B
∈
On
∖
1
𝑜
∧
Lim
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
→
X
⊆
On
77
76
sselda
⊢
A
∈
On
∖
2
𝑜
∧
B
∈
On
∖
1
𝑜
∧
Lim
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
∧
y
∈
X
→
y
∈
On
78
51
eleq2d
⊢
A
∈
On
∖
2
𝑜
∧
B
∈
On
∖
1
𝑜
∧
Lim
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
→
y
∈
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
↔
y
∈
X
79
78
biimpar
⊢
A
∈
On
∖
2
𝑜
∧
B
∈
On
∖
1
𝑜
∧
Lim
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
∧
y
∈
X
→
y
∈
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
80
57
onnminsb
⊢
y
∈
On
→
y
∈
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
→
¬
B
∈
A
↑
𝑜
y
81
77
79
80
sylc
⊢
A
∈
On
∖
2
𝑜
∧
B
∈
On
∖
1
𝑜
∧
Lim
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
∧
y
∈
X
→
¬
B
∈
A
↑
𝑜
y
82
81
nrexdv
⊢
A
∈
On
∖
2
𝑜
∧
B
∈
On
∖
1
𝑜
∧
Lim
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
→
¬
∃
y
∈
X
B
∈
A
↑
𝑜
y
83
73
82
pm2.65da
⊢
A
∈
On
∖
2
𝑜
∧
B
∈
On
∖
1
𝑜
→
¬
Lim
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
84
ioran
⊢
¬
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
=
∅
∨
Lim
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
↔
¬
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
=
∅
∧
¬
Lim
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
85
48
83
84
sylanbrc
⊢
A
∈
On
∖
2
𝑜
∧
B
∈
On
∖
1
𝑜
→
¬
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
=
∅
∨
Lim
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
86
eloni
⊢
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
∈
On
→
Ord
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
87
unizlim
⊢
Ord
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
→
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
=
⋃
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
↔
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
=
∅
∨
Lim
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
88
16
86
87
3syl
⊢
A
∈
On
∖
2
𝑜
∧
B
∈
On
∖
1
𝑜
→
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
=
⋃
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
↔
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
=
∅
∨
Lim
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
89
85
88
mtbird
⊢
A
∈
On
∖
2
𝑜
∧
B
∈
On
∖
1
𝑜
→
¬
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
=
⋃
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
90
orduniorsuc
⊢
Ord
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
→
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
=
⋃
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
∨
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
=
suc
⋃
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
91
16
86
90
3syl
⊢
A
∈
On
∖
2
𝑜
∧
B
∈
On
∖
1
𝑜
→
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
=
⋃
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
∨
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
=
suc
⋃
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
92
91
ord
⊢
A
∈
On
∖
2
𝑜
∧
B
∈
On
∖
1
𝑜
→
¬
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
=
⋃
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
→
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
=
suc
⋃
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
93
89
92
mpd
⊢
A
∈
On
∖
2
𝑜
∧
B
∈
On
∖
1
𝑜
→
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
=
suc
⋃
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
94
23
93
eqtr4id
⊢
A
∈
On
∖
2
𝑜
∧
B
∈
On
∖
1
𝑜
→
suc
X
=
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
95
21
94
eleqtrd
⊢
A
∈
On
∖
2
𝑜
∧
B
∈
On
∖
1
𝑜
→
X
∈
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
96
58
inteqi
⊢
⋂
x
∈
On
|
B
∈
A
↑
𝑜
x
=
⋂
y
∈
On
|
B
∈
A
↑
𝑜
y
97
95
96
eleqtrdi
⊢
A
∈
On
∖
2
𝑜
∧
B
∈
On
∖
1
𝑜
→
X
∈
⋂
y
∈
On
|
B
∈
A
↑
𝑜
y
98
55
onnminsb
⊢
X
∈
On
→
X
∈
⋂
y
∈
On
|
B
∈
A
↑
𝑜
y
→
¬
B
∈
A
↑
𝑜
X
99
19
97
98
sylc
⊢
A
∈
On
∖
2
𝑜
∧
B
∈
On
∖
1
𝑜
→
¬
B
∈
A
↑
𝑜
X
100
oecl
⊢
A
∈
On
∧
X
∈
On
→
A
↑
𝑜
X
∈
On
101
39
19
100
syl2anc
⊢
A
∈
On
∖
2
𝑜
∧
B
∈
On
∖
1
𝑜
→
A
↑
𝑜
X
∈
On
102
ontri1
⊢
A
↑
𝑜
X
∈
On
∧
B
∈
On
→
A
↑
𝑜
X
⊆
B
↔
¬
B
∈
A
↑
𝑜
X
103
101
3
102
syl2anc
⊢
A
∈
On
∖
2
𝑜
∧
B
∈
On
∖
1
𝑜
→
A
↑
𝑜
X
⊆
B
↔
¬
B
∈
A
↑
𝑜
X
104
99
103
mpbird
⊢
A
∈
On
∖
2
𝑜
∧
B
∈
On
∖
1
𝑜
→
A
↑
𝑜
X
⊆
B
105
94
31
eqeltrd
⊢
A
∈
On
∖
2
𝑜
∧
B
∈
On
∖
1
𝑜
→
suc
X
∈
x
∈
On
|
B
∈
A
↑
𝑜
x
106
oveq2
⊢
y
=
suc
X
→
A
↑
𝑜
y
=
A
↑
𝑜
suc
X
107
106
eleq2d
⊢
y
=
suc
X
→
B
∈
A
↑
𝑜
y
↔
B
∈
A
↑
𝑜
suc
X
108
107
58
elrab2
⊢
suc
X
∈
x
∈
On
|
B
∈
A
↑
𝑜
x
↔
suc
X
∈
On
∧
B
∈
A
↑
𝑜
suc
X
109
108
simprbi
⊢
suc
X
∈
x
∈
On
|
B
∈
A
↑
𝑜
x
→
B
∈
A
↑
𝑜
suc
X
110
105
109
syl
⊢
A
∈
On
∖
2
𝑜
∧
B
∈
On
∖
1
𝑜
→
B
∈
A
↑
𝑜
suc
X
111
19
104
110
3jca
⊢
A
∈
On
∖
2
𝑜
∧
B
∈
On
∖
1
𝑜
→
X
∈
On
∧
A
↑
𝑜
X
⊆
B
∧
B
∈
A
↑
𝑜
suc
X