Database
ZF (ZERMELO-FRAENKEL) SET THEORY
ZF Set Theory - add the Axiom of Infinity
The Ackermann bijection
ackbij2lem3
Next ⟩
ackbij2lem4
Metamath Proof Explorer
Ascii
Unicode
Theorem
ackbij2lem3
Description:
Lemma for
ackbij2
.
(Contributed by
Stefan O'Rear
, 18-Nov-2014)
Ref
Expression
Hypotheses
ackbij.f
ω
⊢
F
=
x
∈
𝒫
ω
∩
Fin
⟼
card
⋃
y
∈
x
y
×
𝒫
y
ackbij.g
⊢
G
=
x
∈
V
⟼
y
∈
𝒫
dom
x
⟼
F
x
y
Assertion
ackbij2lem3
ω
⊢
A
∈
ω
→
rec
G
∅
A
⊆
rec
G
∅
suc
A
Proof
Step
Hyp
Ref
Expression
1
ackbij.f
ω
⊢
F
=
x
∈
𝒫
ω
∩
Fin
⟼
card
⋃
y
∈
x
y
×
𝒫
y
2
ackbij.g
⊢
G
=
x
∈
V
⟼
y
∈
𝒫
dom
x
⟼
F
x
y
3
fveq2
⊢
a
=
∅
→
rec
G
∅
a
=
rec
G
∅
∅
4
suceq
⊢
a
=
∅
→
suc
a
=
suc
∅
5
4
fveq2d
⊢
a
=
∅
→
rec
G
∅
suc
a
=
rec
G
∅
suc
∅
6
fveq2
⊢
a
=
∅
→
R
1
a
=
R
1
∅
7
5
6
reseq12d
⊢
a
=
∅
→
rec
G
∅
suc
a
↾
R
1
a
=
rec
G
∅
suc
∅
↾
R
1
∅
8
3
7
eqeq12d
⊢
a
=
∅
→
rec
G
∅
a
=
rec
G
∅
suc
a
↾
R
1
a
↔
rec
G
∅
∅
=
rec
G
∅
suc
∅
↾
R
1
∅
9
fveq2
⊢
a
=
b
→
rec
G
∅
a
=
rec
G
∅
b
10
suceq
⊢
a
=
b
→
suc
a
=
suc
b
11
10
fveq2d
⊢
a
=
b
→
rec
G
∅
suc
a
=
rec
G
∅
suc
b
12
fveq2
⊢
a
=
b
→
R
1
a
=
R
1
b
13
11
12
reseq12d
⊢
a
=
b
→
rec
G
∅
suc
a
↾
R
1
a
=
rec
G
∅
suc
b
↾
R
1
b
14
9
13
eqeq12d
⊢
a
=
b
→
rec
G
∅
a
=
rec
G
∅
suc
a
↾
R
1
a
↔
rec
G
∅
b
=
rec
G
∅
suc
b
↾
R
1
b
15
fveq2
⊢
a
=
suc
b
→
rec
G
∅
a
=
rec
G
∅
suc
b
16
suceq
⊢
a
=
suc
b
→
suc
a
=
suc
suc
b
17
16
fveq2d
⊢
a
=
suc
b
→
rec
G
∅
suc
a
=
rec
G
∅
suc
suc
b
18
fveq2
⊢
a
=
suc
b
→
R
1
a
=
R
1
suc
b
19
17
18
reseq12d
⊢
a
=
suc
b
→
rec
G
∅
suc
a
↾
R
1
a
=
rec
G
∅
suc
suc
b
↾
R
1
suc
b
20
15
19
eqeq12d
⊢
a
=
suc
b
→
rec
G
∅
a
=
rec
G
∅
suc
a
↾
R
1
a
↔
rec
G
∅
suc
b
=
rec
G
∅
suc
suc
b
↾
R
1
suc
b
21
fveq2
⊢
a
=
A
→
rec
G
∅
a
=
rec
G
∅
A
22
suceq
⊢
a
=
A
→
suc
a
=
suc
A
23
22
fveq2d
⊢
a
=
A
→
rec
G
∅
suc
a
=
rec
G
∅
suc
A
24
fveq2
⊢
a
=
A
→
R
1
a
=
R
1
A
25
23
24
reseq12d
⊢
a
=
A
→
rec
G
∅
suc
a
↾
R
1
a
=
rec
G
∅
suc
A
↾
R
1
A
26
21
25
eqeq12d
⊢
a
=
A
→
rec
G
∅
a
=
rec
G
∅
suc
a
↾
R
1
a
↔
rec
G
∅
A
=
rec
G
∅
suc
A
↾
R
1
A
27
res0
⊢
rec
G
∅
suc
∅
↾
∅
=
∅
28
r10
⊢
R
1
∅
=
∅
29
28
reseq2i
⊢
rec
G
∅
suc
∅
↾
R
1
∅
=
rec
G
∅
suc
∅
↾
∅
30
0ex
⊢
∅
∈
V
31
30
rdg0
⊢
rec
G
∅
∅
=
∅
32
27
29
31
3eqtr4ri
⊢
rec
G
∅
∅
=
rec
G
∅
suc
∅
↾
R
1
∅
33
peano2
ω
ω
⊢
b
∈
ω
→
suc
b
∈
ω
34
1
2
ackbij2lem2
ω
⊢
suc
b
∈
ω
→
rec
G
∅
suc
b
:
R
1
suc
b
⟶
1-1 onto
card
R
1
suc
b
35
33
34
syl
ω
⊢
b
∈
ω
→
rec
G
∅
suc
b
:
R
1
suc
b
⟶
1-1 onto
card
R
1
suc
b
36
f1ofn
⊢
rec
G
∅
suc
b
:
R
1
suc
b
⟶
1-1 onto
card
R
1
suc
b
→
rec
G
∅
suc
b
Fn
R
1
suc
b
37
35
36
syl
ω
⊢
b
∈
ω
→
rec
G
∅
suc
b
Fn
R
1
suc
b
38
37
adantr
ω
⊢
b
∈
ω
∧
rec
G
∅
b
=
rec
G
∅
suc
b
↾
R
1
b
→
rec
G
∅
suc
b
Fn
R
1
suc
b
39
peano2
ω
ω
⊢
suc
b
∈
ω
→
suc
suc
b
∈
ω
40
1
2
ackbij2lem2
ω
⊢
suc
suc
b
∈
ω
→
rec
G
∅
suc
suc
b
:
R
1
suc
suc
b
⟶
1-1 onto
card
R
1
suc
suc
b
41
f1ofn
⊢
rec
G
∅
suc
suc
b
:
R
1
suc
suc
b
⟶
1-1 onto
card
R
1
suc
suc
b
→
rec
G
∅
suc
suc
b
Fn
R
1
suc
suc
b
42
33
39
40
41
4syl
ω
⊢
b
∈
ω
→
rec
G
∅
suc
suc
b
Fn
R
1
suc
suc
b
43
nnon
ω
⊢
suc
b
∈
ω
→
suc
b
∈
On
44
33
43
syl
ω
⊢
b
∈
ω
→
suc
b
∈
On
45
r1sssuc
⊢
suc
b
∈
On
→
R
1
suc
b
⊆
R
1
suc
suc
b
46
44
45
syl
ω
⊢
b
∈
ω
→
R
1
suc
b
⊆
R
1
suc
suc
b
47
fnssres
⊢
rec
G
∅
suc
suc
b
Fn
R
1
suc
suc
b
∧
R
1
suc
b
⊆
R
1
suc
suc
b
→
rec
G
∅
suc
suc
b
↾
R
1
suc
b
Fn
R
1
suc
b
48
42
46
47
syl2anc
ω
⊢
b
∈
ω
→
rec
G
∅
suc
suc
b
↾
R
1
suc
b
Fn
R
1
suc
b
49
48
adantr
ω
⊢
b
∈
ω
∧
rec
G
∅
b
=
rec
G
∅
suc
b
↾
R
1
b
→
rec
G
∅
suc
suc
b
↾
R
1
suc
b
Fn
R
1
suc
b
50
nnon
ω
⊢
b
∈
ω
→
b
∈
On
51
r1suc
⊢
b
∈
On
→
R
1
suc
b
=
𝒫
R
1
b
52
50
51
syl
ω
⊢
b
∈
ω
→
R
1
suc
b
=
𝒫
R
1
b
53
52
eleq2d
ω
⊢
b
∈
ω
→
c
∈
R
1
suc
b
↔
c
∈
𝒫
R
1
b
54
53
biimpa
ω
⊢
b
∈
ω
∧
c
∈
R
1
suc
b
→
c
∈
𝒫
R
1
b
55
54
elpwid
ω
⊢
b
∈
ω
∧
c
∈
R
1
suc
b
→
c
⊆
R
1
b
56
resima2
⊢
c
⊆
R
1
b
→
rec
G
∅
suc
b
↾
R
1
b
c
=
rec
G
∅
suc
b
c
57
55
56
syl
ω
⊢
b
∈
ω
∧
c
∈
R
1
suc
b
→
rec
G
∅
suc
b
↾
R
1
b
c
=
rec
G
∅
suc
b
c
58
57
fveq2d
ω
⊢
b
∈
ω
∧
c
∈
R
1
suc
b
→
F
rec
G
∅
suc
b
↾
R
1
b
c
=
F
rec
G
∅
suc
b
c
59
fvex
⊢
rec
G
∅
suc
b
∈
V
60
59
resex
⊢
rec
G
∅
suc
b
↾
R
1
b
∈
V
61
dmeq
⊢
x
=
rec
G
∅
suc
b
↾
R
1
b
→
dom
x
=
dom
rec
G
∅
suc
b
↾
R
1
b
62
61
pweqd
⊢
x
=
rec
G
∅
suc
b
↾
R
1
b
→
𝒫
dom
x
=
𝒫
dom
rec
G
∅
suc
b
↾
R
1
b
63
imaeq1
⊢
x
=
rec
G
∅
suc
b
↾
R
1
b
→
x
y
=
rec
G
∅
suc
b
↾
R
1
b
y
64
63
fveq2d
⊢
x
=
rec
G
∅
suc
b
↾
R
1
b
→
F
x
y
=
F
rec
G
∅
suc
b
↾
R
1
b
y
65
62
64
mpteq12dv
⊢
x
=
rec
G
∅
suc
b
↾
R
1
b
→
y
∈
𝒫
dom
x
⟼
F
x
y
=
y
∈
𝒫
dom
rec
G
∅
suc
b
↾
R
1
b
⟼
F
rec
G
∅
suc
b
↾
R
1
b
y
66
60
dmex
⊢
dom
rec
G
∅
suc
b
↾
R
1
b
∈
V
67
66
pwex
⊢
𝒫
dom
rec
G
∅
suc
b
↾
R
1
b
∈
V
68
67
mptex
⊢
y
∈
𝒫
dom
rec
G
∅
suc
b
↾
R
1
b
⟼
F
rec
G
∅
suc
b
↾
R
1
b
y
∈
V
69
65
2
68
fvmpt
⊢
rec
G
∅
suc
b
↾
R
1
b
∈
V
→
G
rec
G
∅
suc
b
↾
R
1
b
=
y
∈
𝒫
dom
rec
G
∅
suc
b
↾
R
1
b
⟼
F
rec
G
∅
suc
b
↾
R
1
b
y
70
60
69
ax-mp
⊢
G
rec
G
∅
suc
b
↾
R
1
b
=
y
∈
𝒫
dom
rec
G
∅
suc
b
↾
R
1
b
⟼
F
rec
G
∅
suc
b
↾
R
1
b
y
71
70
fveq1i
⊢
G
rec
G
∅
suc
b
↾
R
1
b
c
=
y
∈
𝒫
dom
rec
G
∅
suc
b
↾
R
1
b
⟼
F
rec
G
∅
suc
b
↾
R
1
b
y
c
72
r1sssuc
⊢
b
∈
On
→
R
1
b
⊆
R
1
suc
b
73
50
72
syl
ω
⊢
b
∈
ω
→
R
1
b
⊆
R
1
suc
b
74
fnssres
⊢
rec
G
∅
suc
b
Fn
R
1
suc
b
∧
R
1
b
⊆
R
1
suc
b
→
rec
G
∅
suc
b
↾
R
1
b
Fn
R
1
b
75
37
73
74
syl2anc
ω
⊢
b
∈
ω
→
rec
G
∅
suc
b
↾
R
1
b
Fn
R
1
b
76
75
fndmd
ω
⊢
b
∈
ω
→
dom
rec
G
∅
suc
b
↾
R
1
b
=
R
1
b
77
76
pweqd
ω
⊢
b
∈
ω
→
𝒫
dom
rec
G
∅
suc
b
↾
R
1
b
=
𝒫
R
1
b
78
77
adantr
ω
⊢
b
∈
ω
∧
c
∈
R
1
suc
b
→
𝒫
dom
rec
G
∅
suc
b
↾
R
1
b
=
𝒫
R
1
b
79
54
78
eleqtrrd
ω
⊢
b
∈
ω
∧
c
∈
R
1
suc
b
→
c
∈
𝒫
dom
rec
G
∅
suc
b
↾
R
1
b
80
imaeq2
⊢
y
=
c
→
rec
G
∅
suc
b
↾
R
1
b
y
=
rec
G
∅
suc
b
↾
R
1
b
c
81
80
fveq2d
⊢
y
=
c
→
F
rec
G
∅
suc
b
↾
R
1
b
y
=
F
rec
G
∅
suc
b
↾
R
1
b
c
82
eqid
⊢
y
∈
𝒫
dom
rec
G
∅
suc
b
↾
R
1
b
⟼
F
rec
G
∅
suc
b
↾
R
1
b
y
=
y
∈
𝒫
dom
rec
G
∅
suc
b
↾
R
1
b
⟼
F
rec
G
∅
suc
b
↾
R
1
b
y
83
fvex
⊢
F
rec
G
∅
suc
b
↾
R
1
b
c
∈
V
84
81
82
83
fvmpt
⊢
c
∈
𝒫
dom
rec
G
∅
suc
b
↾
R
1
b
→
y
∈
𝒫
dom
rec
G
∅
suc
b
↾
R
1
b
⟼
F
rec
G
∅
suc
b
↾
R
1
b
y
c
=
F
rec
G
∅
suc
b
↾
R
1
b
c
85
79
84
syl
ω
⊢
b
∈
ω
∧
c
∈
R
1
suc
b
→
y
∈
𝒫
dom
rec
G
∅
suc
b
↾
R
1
b
⟼
F
rec
G
∅
suc
b
↾
R
1
b
y
c
=
F
rec
G
∅
suc
b
↾
R
1
b
c
86
71
85
eqtrid
ω
⊢
b
∈
ω
∧
c
∈
R
1
suc
b
→
G
rec
G
∅
suc
b
↾
R
1
b
c
=
F
rec
G
∅
suc
b
↾
R
1
b
c
87
dmeq
⊢
x
=
rec
G
∅
suc
b
→
dom
x
=
dom
rec
G
∅
suc
b
88
87
pweqd
⊢
x
=
rec
G
∅
suc
b
→
𝒫
dom
x
=
𝒫
dom
rec
G
∅
suc
b
89
imaeq1
⊢
x
=
rec
G
∅
suc
b
→
x
y
=
rec
G
∅
suc
b
y
90
89
fveq2d
⊢
x
=
rec
G
∅
suc
b
→
F
x
y
=
F
rec
G
∅
suc
b
y
91
88
90
mpteq12dv
⊢
x
=
rec
G
∅
suc
b
→
y
∈
𝒫
dom
x
⟼
F
x
y
=
y
∈
𝒫
dom
rec
G
∅
suc
b
⟼
F
rec
G
∅
suc
b
y
92
59
dmex
⊢
dom
rec
G
∅
suc
b
∈
V
93
92
pwex
⊢
𝒫
dom
rec
G
∅
suc
b
∈
V
94
93
mptex
⊢
y
∈
𝒫
dom
rec
G
∅
suc
b
⟼
F
rec
G
∅
suc
b
y
∈
V
95
91
2
94
fvmpt
⊢
rec
G
∅
suc
b
∈
V
→
G
rec
G
∅
suc
b
=
y
∈
𝒫
dom
rec
G
∅
suc
b
⟼
F
rec
G
∅
suc
b
y
96
59
95
ax-mp
⊢
G
rec
G
∅
suc
b
=
y
∈
𝒫
dom
rec
G
∅
suc
b
⟼
F
rec
G
∅
suc
b
y
97
96
fveq1i
⊢
G
rec
G
∅
suc
b
c
=
y
∈
𝒫
dom
rec
G
∅
suc
b
⟼
F
rec
G
∅
suc
b
y
c
98
r1tr
⊢
Tr
R
1
suc
b
99
98
a1i
ω
⊢
b
∈
ω
→
Tr
R
1
suc
b
100
dftr4
⊢
Tr
R
1
suc
b
↔
R
1
suc
b
⊆
𝒫
R
1
suc
b
101
99
100
sylib
ω
⊢
b
∈
ω
→
R
1
suc
b
⊆
𝒫
R
1
suc
b
102
101
sselda
ω
⊢
b
∈
ω
∧
c
∈
R
1
suc
b
→
c
∈
𝒫
R
1
suc
b
103
f1odm
⊢
rec
G
∅
suc
b
:
R
1
suc
b
⟶
1-1 onto
card
R
1
suc
b
→
dom
rec
G
∅
suc
b
=
R
1
suc
b
104
35
103
syl
ω
⊢
b
∈
ω
→
dom
rec
G
∅
suc
b
=
R
1
suc
b
105
104
pweqd
ω
⊢
b
∈
ω
→
𝒫
dom
rec
G
∅
suc
b
=
𝒫
R
1
suc
b
106
105
adantr
ω
⊢
b
∈
ω
∧
c
∈
R
1
suc
b
→
𝒫
dom
rec
G
∅
suc
b
=
𝒫
R
1
suc
b
107
102
106
eleqtrrd
ω
⊢
b
∈
ω
∧
c
∈
R
1
suc
b
→
c
∈
𝒫
dom
rec
G
∅
suc
b
108
imaeq2
⊢
y
=
c
→
rec
G
∅
suc
b
y
=
rec
G
∅
suc
b
c
109
108
fveq2d
⊢
y
=
c
→
F
rec
G
∅
suc
b
y
=
F
rec
G
∅
suc
b
c
110
eqid
⊢
y
∈
𝒫
dom
rec
G
∅
suc
b
⟼
F
rec
G
∅
suc
b
y
=
y
∈
𝒫
dom
rec
G
∅
suc
b
⟼
F
rec
G
∅
suc
b
y
111
fvex
⊢
F
rec
G
∅
suc
b
c
∈
V
112
109
110
111
fvmpt
⊢
c
∈
𝒫
dom
rec
G
∅
suc
b
→
y
∈
𝒫
dom
rec
G
∅
suc
b
⟼
F
rec
G
∅
suc
b
y
c
=
F
rec
G
∅
suc
b
c
113
107
112
syl
ω
⊢
b
∈
ω
∧
c
∈
R
1
suc
b
→
y
∈
𝒫
dom
rec
G
∅
suc
b
⟼
F
rec
G
∅
suc
b
y
c
=
F
rec
G
∅
suc
b
c
114
97
113
eqtrid
ω
⊢
b
∈
ω
∧
c
∈
R
1
suc
b
→
G
rec
G
∅
suc
b
c
=
F
rec
G
∅
suc
b
c
115
58
86
114
3eqtr4d
ω
⊢
b
∈
ω
∧
c
∈
R
1
suc
b
→
G
rec
G
∅
suc
b
↾
R
1
b
c
=
G
rec
G
∅
suc
b
c
116
115
adantlr
ω
⊢
b
∈
ω
∧
rec
G
∅
b
=
rec
G
∅
suc
b
↾
R
1
b
∧
c
∈
R
1
suc
b
→
G
rec
G
∅
suc
b
↾
R
1
b
c
=
G
rec
G
∅
suc
b
c
117
fveq2
⊢
rec
G
∅
b
=
rec
G
∅
suc
b
↾
R
1
b
→
G
rec
G
∅
b
=
G
rec
G
∅
suc
b
↾
R
1
b
118
117
fveq1d
⊢
rec
G
∅
b
=
rec
G
∅
suc
b
↾
R
1
b
→
G
rec
G
∅
b
c
=
G
rec
G
∅
suc
b
↾
R
1
b
c
119
118
ad2antlr
ω
⊢
b
∈
ω
∧
rec
G
∅
b
=
rec
G
∅
suc
b
↾
R
1
b
∧
c
∈
R
1
suc
b
→
G
rec
G
∅
b
c
=
G
rec
G
∅
suc
b
↾
R
1
b
c
120
rdgsuc
⊢
suc
b
∈
On
→
rec
G
∅
suc
suc
b
=
G
rec
G
∅
suc
b
121
44
120
syl
ω
⊢
b
∈
ω
→
rec
G
∅
suc
suc
b
=
G
rec
G
∅
suc
b
122
121
fveq1d
ω
⊢
b
∈
ω
→
rec
G
∅
suc
suc
b
c
=
G
rec
G
∅
suc
b
c
123
122
ad2antrr
ω
⊢
b
∈
ω
∧
rec
G
∅
b
=
rec
G
∅
suc
b
↾
R
1
b
∧
c
∈
R
1
suc
b
→
rec
G
∅
suc
suc
b
c
=
G
rec
G
∅
suc
b
c
124
116
119
123
3eqtr4rd
ω
⊢
b
∈
ω
∧
rec
G
∅
b
=
rec
G
∅
suc
b
↾
R
1
b
∧
c
∈
R
1
suc
b
→
rec
G
∅
suc
suc
b
c
=
G
rec
G
∅
b
c
125
fvres
⊢
c
∈
R
1
suc
b
→
rec
G
∅
suc
suc
b
↾
R
1
suc
b
c
=
rec
G
∅
suc
suc
b
c
126
125
adantl
ω
⊢
b
∈
ω
∧
rec
G
∅
b
=
rec
G
∅
suc
b
↾
R
1
b
∧
c
∈
R
1
suc
b
→
rec
G
∅
suc
suc
b
↾
R
1
suc
b
c
=
rec
G
∅
suc
suc
b
c
127
rdgsuc
⊢
b
∈
On
→
rec
G
∅
suc
b
=
G
rec
G
∅
b
128
50
127
syl
ω
⊢
b
∈
ω
→
rec
G
∅
suc
b
=
G
rec
G
∅
b
129
128
fveq1d
ω
⊢
b
∈
ω
→
rec
G
∅
suc
b
c
=
G
rec
G
∅
b
c
130
129
ad2antrr
ω
⊢
b
∈
ω
∧
rec
G
∅
b
=
rec
G
∅
suc
b
↾
R
1
b
∧
c
∈
R
1
suc
b
→
rec
G
∅
suc
b
c
=
G
rec
G
∅
b
c
131
124
126
130
3eqtr4rd
ω
⊢
b
∈
ω
∧
rec
G
∅
b
=
rec
G
∅
suc
b
↾
R
1
b
∧
c
∈
R
1
suc
b
→
rec
G
∅
suc
b
c
=
rec
G
∅
suc
suc
b
↾
R
1
suc
b
c
132
38
49
131
eqfnfvd
ω
⊢
b
∈
ω
∧
rec
G
∅
b
=
rec
G
∅
suc
b
↾
R
1
b
→
rec
G
∅
suc
b
=
rec
G
∅
suc
suc
b
↾
R
1
suc
b
133
132
ex
ω
⊢
b
∈
ω
→
rec
G
∅
b
=
rec
G
∅
suc
b
↾
R
1
b
→
rec
G
∅
suc
b
=
rec
G
∅
suc
suc
b
↾
R
1
suc
b
134
8
14
20
26
32
133
finds
ω
⊢
A
∈
ω
→
rec
G
∅
A
=
rec
G
∅
suc
A
↾
R
1
A
135
resss
⊢
rec
G
∅
suc
A
↾
R
1
A
⊆
rec
G
∅
suc
A
136
134
135
eqsstrdi
ω
⊢
A
∈
ω
→
rec
G
∅
A
⊆
rec
G
∅
suc
A