Database
ZF (ZERMELO-FRAENKEL) SET THEORY
ZF Set Theory - add the Axiom of Union
Ordinal arithmetic
oeoelem
Next ⟩
oeoe
Metamath Proof Explorer
Ascii
Unicode
Theorem
oeoelem
Description:
Lemma for
oeoe
.
(Contributed by
Eric Schmidt
, 26-May-2009)
Ref
Expression
Hypotheses
oeoelem.1
⊢
A
∈
On
oeoelem.2
⊢
∅
∈
A
Assertion
oeoelem
⊢
B
∈
On
∧
C
∈
On
→
A
↑
𝑜
B
↑
𝑜
C
=
A
↑
𝑜
B
⋅
𝑜
C
Proof
Step
Hyp
Ref
Expression
1
oeoelem.1
⊢
A
∈
On
2
oeoelem.2
⊢
∅
∈
A
3
oveq2
⊢
x
=
∅
→
A
↑
𝑜
B
↑
𝑜
x
=
A
↑
𝑜
B
↑
𝑜
∅
4
oveq2
⊢
x
=
∅
→
B
⋅
𝑜
x
=
B
⋅
𝑜
∅
5
4
oveq2d
⊢
x
=
∅
→
A
↑
𝑜
B
⋅
𝑜
x
=
A
↑
𝑜
B
⋅
𝑜
∅
6
3
5
eqeq12d
⊢
x
=
∅
→
A
↑
𝑜
B
↑
𝑜
x
=
A
↑
𝑜
B
⋅
𝑜
x
↔
A
↑
𝑜
B
↑
𝑜
∅
=
A
↑
𝑜
B
⋅
𝑜
∅
7
oveq2
⊢
x
=
y
→
A
↑
𝑜
B
↑
𝑜
x
=
A
↑
𝑜
B
↑
𝑜
y
8
oveq2
⊢
x
=
y
→
B
⋅
𝑜
x
=
B
⋅
𝑜
y
9
8
oveq2d
⊢
x
=
y
→
A
↑
𝑜
B
⋅
𝑜
x
=
A
↑
𝑜
B
⋅
𝑜
y
10
7
9
eqeq12d
⊢
x
=
y
→
A
↑
𝑜
B
↑
𝑜
x
=
A
↑
𝑜
B
⋅
𝑜
x
↔
A
↑
𝑜
B
↑
𝑜
y
=
A
↑
𝑜
B
⋅
𝑜
y
11
oveq2
⊢
x
=
suc
y
→
A
↑
𝑜
B
↑
𝑜
x
=
A
↑
𝑜
B
↑
𝑜
suc
y
12
oveq2
⊢
x
=
suc
y
→
B
⋅
𝑜
x
=
B
⋅
𝑜
suc
y
13
12
oveq2d
⊢
x
=
suc
y
→
A
↑
𝑜
B
⋅
𝑜
x
=
A
↑
𝑜
B
⋅
𝑜
suc
y
14
11
13
eqeq12d
⊢
x
=
suc
y
→
A
↑
𝑜
B
↑
𝑜
x
=
A
↑
𝑜
B
⋅
𝑜
x
↔
A
↑
𝑜
B
↑
𝑜
suc
y
=
A
↑
𝑜
B
⋅
𝑜
suc
y
15
oveq2
⊢
x
=
C
→
A
↑
𝑜
B
↑
𝑜
x
=
A
↑
𝑜
B
↑
𝑜
C
16
oveq2
⊢
x
=
C
→
B
⋅
𝑜
x
=
B
⋅
𝑜
C
17
16
oveq2d
⊢
x
=
C
→
A
↑
𝑜
B
⋅
𝑜
x
=
A
↑
𝑜
B
⋅
𝑜
C
18
15
17
eqeq12d
⊢
x
=
C
→
A
↑
𝑜
B
↑
𝑜
x
=
A
↑
𝑜
B
⋅
𝑜
x
↔
A
↑
𝑜
B
↑
𝑜
C
=
A
↑
𝑜
B
⋅
𝑜
C
19
oecl
⊢
A
∈
On
∧
B
∈
On
→
A
↑
𝑜
B
∈
On
20
1
19
mpan
⊢
B
∈
On
→
A
↑
𝑜
B
∈
On
21
oe0
⊢
A
↑
𝑜
B
∈
On
→
A
↑
𝑜
B
↑
𝑜
∅
=
1
𝑜
22
20
21
syl
⊢
B
∈
On
→
A
↑
𝑜
B
↑
𝑜
∅
=
1
𝑜
23
om0
⊢
B
∈
On
→
B
⋅
𝑜
∅
=
∅
24
23
oveq2d
⊢
B
∈
On
→
A
↑
𝑜
B
⋅
𝑜
∅
=
A
↑
𝑜
∅
25
oe0
⊢
A
∈
On
→
A
↑
𝑜
∅
=
1
𝑜
26
1
25
ax-mp
⊢
A
↑
𝑜
∅
=
1
𝑜
27
24
26
eqtrdi
⊢
B
∈
On
→
A
↑
𝑜
B
⋅
𝑜
∅
=
1
𝑜
28
22
27
eqtr4d
⊢
B
∈
On
→
A
↑
𝑜
B
↑
𝑜
∅
=
A
↑
𝑜
B
⋅
𝑜
∅
29
oveq1
⊢
A
↑
𝑜
B
↑
𝑜
y
=
A
↑
𝑜
B
⋅
𝑜
y
→
A
↑
𝑜
B
↑
𝑜
y
⋅
𝑜
A
↑
𝑜
B
=
A
↑
𝑜
B
⋅
𝑜
y
⋅
𝑜
A
↑
𝑜
B
30
oesuc
⊢
A
↑
𝑜
B
∈
On
∧
y
∈
On
→
A
↑
𝑜
B
↑
𝑜
suc
y
=
A
↑
𝑜
B
↑
𝑜
y
⋅
𝑜
A
↑
𝑜
B
31
20
30
sylan
⊢
B
∈
On
∧
y
∈
On
→
A
↑
𝑜
B
↑
𝑜
suc
y
=
A
↑
𝑜
B
↑
𝑜
y
⋅
𝑜
A
↑
𝑜
B
32
omsuc
⊢
B
∈
On
∧
y
∈
On
→
B
⋅
𝑜
suc
y
=
B
⋅
𝑜
y
+
𝑜
B
33
32
oveq2d
⊢
B
∈
On
∧
y
∈
On
→
A
↑
𝑜
B
⋅
𝑜
suc
y
=
A
↑
𝑜
B
⋅
𝑜
y
+
𝑜
B
34
omcl
⊢
B
∈
On
∧
y
∈
On
→
B
⋅
𝑜
y
∈
On
35
oeoa
⊢
A
∈
On
∧
B
⋅
𝑜
y
∈
On
∧
B
∈
On
→
A
↑
𝑜
B
⋅
𝑜
y
+
𝑜
B
=
A
↑
𝑜
B
⋅
𝑜
y
⋅
𝑜
A
↑
𝑜
B
36
1
35
mp3an1
⊢
B
⋅
𝑜
y
∈
On
∧
B
∈
On
→
A
↑
𝑜
B
⋅
𝑜
y
+
𝑜
B
=
A
↑
𝑜
B
⋅
𝑜
y
⋅
𝑜
A
↑
𝑜
B
37
34
36
sylan
⊢
B
∈
On
∧
y
∈
On
∧
B
∈
On
→
A
↑
𝑜
B
⋅
𝑜
y
+
𝑜
B
=
A
↑
𝑜
B
⋅
𝑜
y
⋅
𝑜
A
↑
𝑜
B
38
37
anabss1
⊢
B
∈
On
∧
y
∈
On
→
A
↑
𝑜
B
⋅
𝑜
y
+
𝑜
B
=
A
↑
𝑜
B
⋅
𝑜
y
⋅
𝑜
A
↑
𝑜
B
39
33
38
eqtrd
⊢
B
∈
On
∧
y
∈
On
→
A
↑
𝑜
B
⋅
𝑜
suc
y
=
A
↑
𝑜
B
⋅
𝑜
y
⋅
𝑜
A
↑
𝑜
B
40
31
39
eqeq12d
⊢
B
∈
On
∧
y
∈
On
→
A
↑
𝑜
B
↑
𝑜
suc
y
=
A
↑
𝑜
B
⋅
𝑜
suc
y
↔
A
↑
𝑜
B
↑
𝑜
y
⋅
𝑜
A
↑
𝑜
B
=
A
↑
𝑜
B
⋅
𝑜
y
⋅
𝑜
A
↑
𝑜
B
41
29
40
imbitrrid
⊢
B
∈
On
∧
y
∈
On
→
A
↑
𝑜
B
↑
𝑜
y
=
A
↑
𝑜
B
⋅
𝑜
y
→
A
↑
𝑜
B
↑
𝑜
suc
y
=
A
↑
𝑜
B
⋅
𝑜
suc
y
42
41
expcom
⊢
y
∈
On
→
B
∈
On
→
A
↑
𝑜
B
↑
𝑜
y
=
A
↑
𝑜
B
⋅
𝑜
y
→
A
↑
𝑜
B
↑
𝑜
suc
y
=
A
↑
𝑜
B
⋅
𝑜
suc
y
43
iuneq2
⊢
∀
y
∈
x
A
↑
𝑜
B
↑
𝑜
y
=
A
↑
𝑜
B
⋅
𝑜
y
→
⋃
y
∈
x
A
↑
𝑜
B
↑
𝑜
y
=
⋃
y
∈
x
A
↑
𝑜
B
⋅
𝑜
y
44
vex
⊢
x
∈
V
45
oen0
⊢
A
∈
On
∧
B
∈
On
∧
∅
∈
A
→
∅
∈
A
↑
𝑜
B
46
2
45
mpan2
⊢
A
∈
On
∧
B
∈
On
→
∅
∈
A
↑
𝑜
B
47
oelim
⊢
A
↑
𝑜
B
∈
On
∧
x
∈
V
∧
Lim
x
∧
∅
∈
A
↑
𝑜
B
→
A
↑
𝑜
B
↑
𝑜
x
=
⋃
y
∈
x
A
↑
𝑜
B
↑
𝑜
y
48
19
47
sylanl1
⊢
A
∈
On
∧
B
∈
On
∧
x
∈
V
∧
Lim
x
∧
∅
∈
A
↑
𝑜
B
→
A
↑
𝑜
B
↑
𝑜
x
=
⋃
y
∈
x
A
↑
𝑜
B
↑
𝑜
y
49
46
48
mpidan
⊢
A
∈
On
∧
B
∈
On
∧
x
∈
V
∧
Lim
x
→
A
↑
𝑜
B
↑
𝑜
x
=
⋃
y
∈
x
A
↑
𝑜
B
↑
𝑜
y
50
1
49
mpanl1
⊢
B
∈
On
∧
x
∈
V
∧
Lim
x
→
A
↑
𝑜
B
↑
𝑜
x
=
⋃
y
∈
x
A
↑
𝑜
B
↑
𝑜
y
51
44
50
mpanr1
⊢
B
∈
On
∧
Lim
x
→
A
↑
𝑜
B
↑
𝑜
x
=
⋃
y
∈
x
A
↑
𝑜
B
↑
𝑜
y
52
omlim
⊢
B
∈
On
∧
x
∈
V
∧
Lim
x
→
B
⋅
𝑜
x
=
⋃
y
∈
x
B
⋅
𝑜
y
53
44
52
mpanr1
⊢
B
∈
On
∧
Lim
x
→
B
⋅
𝑜
x
=
⋃
y
∈
x
B
⋅
𝑜
y
54
53
oveq2d
⊢
B
∈
On
∧
Lim
x
→
A
↑
𝑜
B
⋅
𝑜
x
=
A
↑
𝑜
⋃
y
∈
x
B
⋅
𝑜
y
55
limord
⊢
Lim
x
→
Ord
x
56
ordelon
⊢
Ord
x
∧
y
∈
x
→
y
∈
On
57
55
56
sylan
⊢
Lim
x
∧
y
∈
x
→
y
∈
On
58
57
34
sylan2
⊢
B
∈
On
∧
Lim
x
∧
y
∈
x
→
B
⋅
𝑜
y
∈
On
59
58
anassrs
⊢
B
∈
On
∧
Lim
x
∧
y
∈
x
→
B
⋅
𝑜
y
∈
On
60
59
ralrimiva
⊢
B
∈
On
∧
Lim
x
→
∀
y
∈
x
B
⋅
𝑜
y
∈
On
61
0ellim
⊢
Lim
x
→
∅
∈
x
62
61
ne0d
⊢
Lim
x
→
x
≠
∅
63
62
adantl
⊢
B
∈
On
∧
Lim
x
→
x
≠
∅
64
vex
⊢
w
∈
V
65
oelim
⊢
A
∈
On
∧
w
∈
V
∧
Lim
w
∧
∅
∈
A
→
A
↑
𝑜
w
=
⋃
z
∈
w
A
↑
𝑜
z
66
2
65
mpan2
⊢
A
∈
On
∧
w
∈
V
∧
Lim
w
→
A
↑
𝑜
w
=
⋃
z
∈
w
A
↑
𝑜
z
67
1
66
mpan
⊢
w
∈
V
∧
Lim
w
→
A
↑
𝑜
w
=
⋃
z
∈
w
A
↑
𝑜
z
68
64
67
mpan
⊢
Lim
w
→
A
↑
𝑜
w
=
⋃
z
∈
w
A
↑
𝑜
z
69
oewordi
⊢
z
∈
On
∧
w
∈
On
∧
A
∈
On
∧
∅
∈
A
→
z
⊆
w
→
A
↑
𝑜
z
⊆
A
↑
𝑜
w
70
2
69
mpan2
⊢
z
∈
On
∧
w
∈
On
∧
A
∈
On
→
z
⊆
w
→
A
↑
𝑜
z
⊆
A
↑
𝑜
w
71
1
70
mp3an3
⊢
z
∈
On
∧
w
∈
On
→
z
⊆
w
→
A
↑
𝑜
z
⊆
A
↑
𝑜
w
72
71
3impia
⊢
z
∈
On
∧
w
∈
On
∧
z
⊆
w
→
A
↑
𝑜
z
⊆
A
↑
𝑜
w
73
68
72
onoviun
⊢
x
∈
V
∧
∀
y
∈
x
B
⋅
𝑜
y
∈
On
∧
x
≠
∅
→
A
↑
𝑜
⋃
y
∈
x
B
⋅
𝑜
y
=
⋃
y
∈
x
A
↑
𝑜
B
⋅
𝑜
y
74
44
60
63
73
mp3an2i
⊢
B
∈
On
∧
Lim
x
→
A
↑
𝑜
⋃
y
∈
x
B
⋅
𝑜
y
=
⋃
y
∈
x
A
↑
𝑜
B
⋅
𝑜
y
75
54
74
eqtrd
⊢
B
∈
On
∧
Lim
x
→
A
↑
𝑜
B
⋅
𝑜
x
=
⋃
y
∈
x
A
↑
𝑜
B
⋅
𝑜
y
76
51
75
eqeq12d
⊢
B
∈
On
∧
Lim
x
→
A
↑
𝑜
B
↑
𝑜
x
=
A
↑
𝑜
B
⋅
𝑜
x
↔
⋃
y
∈
x
A
↑
𝑜
B
↑
𝑜
y
=
⋃
y
∈
x
A
↑
𝑜
B
⋅
𝑜
y
77
43
76
imbitrrid
⊢
B
∈
On
∧
Lim
x
→
∀
y
∈
x
A
↑
𝑜
B
↑
𝑜
y
=
A
↑
𝑜
B
⋅
𝑜
y
→
A
↑
𝑜
B
↑
𝑜
x
=
A
↑
𝑜
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78
77
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79
6
10
14
18
28
42
78
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80
79
impcom
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