Database
SUPPLEMENTARY MATERIAL (USERS' MATHBOXES)
Mathbox for Stefan O'Rear
Diophantine sets 2 miscellanea
lzenom
Next ⟩
elmapresaunres2
Metamath Proof Explorer
Ascii
Unicode
Theorem
lzenom
Description:
Lower integers are countably infinite.
(Contributed by
Stefan O'Rear
, 10-Oct-2014)
Ref
Expression
Assertion
lzenom
ω
⊢
N
∈
ℤ
→
ℤ
∖
ℤ
≥
N
+
1
≈
ω
Proof
Step
Hyp
Ref
Expression
1
zex
⊢
ℤ
∈
V
2
difexg
⊢
ℤ
∈
V
→
ℤ
∖
ℤ
≥
N
+
1
∈
V
3
1
2
mp1i
⊢
N
∈
ℤ
→
ℤ
∖
ℤ
≥
N
+
1
∈
V
4
nnex
⊢
ℕ
∈
V
5
4
a1i
⊢
N
∈
ℤ
→
ℕ
∈
V
6
ovex
⊢
N
+
1
-
a
∈
V
7
6
2a1i
⊢
N
∈
ℤ
→
a
∈
ℤ
∖
ℤ
≥
N
+
1
→
N
+
1
-
a
∈
V
8
ovex
⊢
N
+
1
-
b
∈
V
9
8
2a1i
⊢
N
∈
ℤ
→
b
∈
ℕ
→
N
+
1
-
b
∈
V
10
simpl
⊢
N
∈
ℤ
∧
a
∈
ℤ
∧
a
≤
N
→
N
∈
ℤ
11
10
peano2zd
⊢
N
∈
ℤ
∧
a
∈
ℤ
∧
a
≤
N
→
N
+
1
∈
ℤ
12
simprl
⊢
N
∈
ℤ
∧
a
∈
ℤ
∧
a
≤
N
→
a
∈
ℤ
13
11
12
zsubcld
⊢
N
∈
ℤ
∧
a
∈
ℤ
∧
a
≤
N
→
N
+
1
-
a
∈
ℤ
14
zre
⊢
a
∈
ℤ
→
a
∈
ℝ
15
14
ad2antrl
⊢
N
∈
ℤ
∧
a
∈
ℤ
∧
a
≤
N
→
a
∈
ℝ
16
11
zred
⊢
N
∈
ℤ
∧
a
∈
ℤ
∧
a
≤
N
→
N
+
1
∈
ℝ
17
1red
⊢
N
∈
ℤ
∧
a
∈
ℤ
∧
a
≤
N
→
1
∈
ℝ
18
simprr
⊢
N
∈
ℤ
∧
a
∈
ℤ
∧
a
≤
N
→
a
≤
N
19
zcn
⊢
N
∈
ℤ
→
N
∈
ℂ
20
19
adantr
⊢
N
∈
ℤ
∧
a
∈
ℤ
∧
a
≤
N
→
N
∈
ℂ
21
ax-1cn
⊢
1
∈
ℂ
22
pncan
⊢
N
∈
ℂ
∧
1
∈
ℂ
→
N
+
1
-
1
=
N
23
20
21
22
sylancl
⊢
N
∈
ℤ
∧
a
∈
ℤ
∧
a
≤
N
→
N
+
1
-
1
=
N
24
18
23
breqtrrd
⊢
N
∈
ℤ
∧
a
∈
ℤ
∧
a
≤
N
→
a
≤
N
+
1
-
1
25
15
16
17
24
lesubd
⊢
N
∈
ℤ
∧
a
∈
ℤ
∧
a
≤
N
→
1
≤
N
+
1
-
a
26
11
zcnd
⊢
N
∈
ℤ
∧
a
∈
ℤ
∧
a
≤
N
→
N
+
1
∈
ℂ
27
zcn
⊢
a
∈
ℤ
→
a
∈
ℂ
28
27
ad2antrl
⊢
N
∈
ℤ
∧
a
∈
ℤ
∧
a
≤
N
→
a
∈
ℂ
29
26
28
nncand
⊢
N
∈
ℤ
∧
a
∈
ℤ
∧
a
≤
N
→
N
+
1
-
N
+
1
-
a
=
a
30
29
eqcomd
⊢
N
∈
ℤ
∧
a
∈
ℤ
∧
a
≤
N
→
a
=
N
+
1
-
N
+
1
-
a
31
13
25
30
jca31
⊢
N
∈
ℤ
∧
a
∈
ℤ
∧
a
≤
N
→
N
+
1
-
a
∈
ℤ
∧
1
≤
N
+
1
-
a
∧
a
=
N
+
1
-
N
+
1
-
a
32
31
adantrr
⊢
N
∈
ℤ
∧
a
∈
ℤ
∧
a
≤
N
∧
b
=
N
+
1
-
a
→
N
+
1
-
a
∈
ℤ
∧
1
≤
N
+
1
-
a
∧
a
=
N
+
1
-
N
+
1
-
a
33
eleq1
⊢
b
=
N
+
1
-
a
→
b
∈
ℤ
↔
N
+
1
-
a
∈
ℤ
34
breq2
⊢
b
=
N
+
1
-
a
→
1
≤
b
↔
1
≤
N
+
1
-
a
35
33
34
anbi12d
⊢
b
=
N
+
1
-
a
→
b
∈
ℤ
∧
1
≤
b
↔
N
+
1
-
a
∈
ℤ
∧
1
≤
N
+
1
-
a
36
oveq2
⊢
b
=
N
+
1
-
a
→
N
+
1
-
b
=
N
+
1
-
N
+
1
-
a
37
36
eqeq2d
⊢
b
=
N
+
1
-
a
→
a
=
N
+
1
-
b
↔
a
=
N
+
1
-
N
+
1
-
a
38
35
37
anbi12d
⊢
b
=
N
+
1
-
a
→
b
∈
ℤ
∧
1
≤
b
∧
a
=
N
+
1
-
b
↔
N
+
1
-
a
∈
ℤ
∧
1
≤
N
+
1
-
a
∧
a
=
N
+
1
-
N
+
1
-
a
39
38
ad2antll
⊢
N
∈
ℤ
∧
a
∈
ℤ
∧
a
≤
N
∧
b
=
N
+
1
-
a
→
b
∈
ℤ
∧
1
≤
b
∧
a
=
N
+
1
-
b
↔
N
+
1
-
a
∈
ℤ
∧
1
≤
N
+
1
-
a
∧
a
=
N
+
1
-
N
+
1
-
a
40
32
39
mpbird
⊢
N
∈
ℤ
∧
a
∈
ℤ
∧
a
≤
N
∧
b
=
N
+
1
-
a
→
b
∈
ℤ
∧
1
≤
b
∧
a
=
N
+
1
-
b
41
simpl
⊢
N
∈
ℤ
∧
b
∈
ℤ
∧
1
≤
b
→
N
∈
ℤ
42
41
peano2zd
⊢
N
∈
ℤ
∧
b
∈
ℤ
∧
1
≤
b
→
N
+
1
∈
ℤ
43
simprl
⊢
N
∈
ℤ
∧
b
∈
ℤ
∧
1
≤
b
→
b
∈
ℤ
44
42
43
zsubcld
⊢
N
∈
ℤ
∧
b
∈
ℤ
∧
1
≤
b
→
N
+
1
-
b
∈
ℤ
45
42
zred
⊢
N
∈
ℤ
∧
b
∈
ℤ
∧
1
≤
b
→
N
+
1
∈
ℝ
46
zre
⊢
N
∈
ℤ
→
N
∈
ℝ
47
46
adantr
⊢
N
∈
ℤ
∧
b
∈
ℤ
∧
1
≤
b
→
N
∈
ℝ
48
zre
⊢
b
∈
ℤ
→
b
∈
ℝ
49
48
ad2antrl
⊢
N
∈
ℤ
∧
b
∈
ℤ
∧
1
≤
b
→
b
∈
ℝ
50
47
recnd
⊢
N
∈
ℤ
∧
b
∈
ℤ
∧
1
≤
b
→
N
∈
ℂ
51
pncan2
⊢
N
∈
ℂ
∧
1
∈
ℂ
→
N
+
1
-
N
=
1
52
50
21
51
sylancl
⊢
N
∈
ℤ
∧
b
∈
ℤ
∧
1
≤
b
→
N
+
1
-
N
=
1
53
simprr
⊢
N
∈
ℤ
∧
b
∈
ℤ
∧
1
≤
b
→
1
≤
b
54
52
53
eqbrtrd
⊢
N
∈
ℤ
∧
b
∈
ℤ
∧
1
≤
b
→
N
+
1
-
N
≤
b
55
45
47
49
54
subled
⊢
N
∈
ℤ
∧
b
∈
ℤ
∧
1
≤
b
→
N
+
1
-
b
≤
N
56
42
zcnd
⊢
N
∈
ℤ
∧
b
∈
ℤ
∧
1
≤
b
→
N
+
1
∈
ℂ
57
zcn
⊢
b
∈
ℤ
→
b
∈
ℂ
58
57
ad2antrl
⊢
N
∈
ℤ
∧
b
∈
ℤ
∧
1
≤
b
→
b
∈
ℂ
59
56
58
nncand
⊢
N
∈
ℤ
∧
b
∈
ℤ
∧
1
≤
b
→
N
+
1
-
N
+
1
-
b
=
b
60
59
eqcomd
⊢
N
∈
ℤ
∧
b
∈
ℤ
∧
1
≤
b
→
b
=
N
+
1
-
N
+
1
-
b
61
44
55
60
jca31
⊢
N
∈
ℤ
∧
b
∈
ℤ
∧
1
≤
b
→
N
+
1
-
b
∈
ℤ
∧
N
+
1
-
b
≤
N
∧
b
=
N
+
1
-
N
+
1
-
b
62
61
adantrr
⊢
N
∈
ℤ
∧
b
∈
ℤ
∧
1
≤
b
∧
a
=
N
+
1
-
b
→
N
+
1
-
b
∈
ℤ
∧
N
+
1
-
b
≤
N
∧
b
=
N
+
1
-
N
+
1
-
b
63
eleq1
⊢
a
=
N
+
1
-
b
→
a
∈
ℤ
↔
N
+
1
-
b
∈
ℤ
64
breq1
⊢
a
=
N
+
1
-
b
→
a
≤
N
↔
N
+
1
-
b
≤
N
65
63
64
anbi12d
⊢
a
=
N
+
1
-
b
→
a
∈
ℤ
∧
a
≤
N
↔
N
+
1
-
b
∈
ℤ
∧
N
+
1
-
b
≤
N
66
oveq2
⊢
a
=
N
+
1
-
b
→
N
+
1
-
a
=
N
+
1
-
N
+
1
-
b
67
66
eqeq2d
⊢
a
=
N
+
1
-
b
→
b
=
N
+
1
-
a
↔
b
=
N
+
1
-
N
+
1
-
b
68
65
67
anbi12d
⊢
a
=
N
+
1
-
b
→
a
∈
ℤ
∧
a
≤
N
∧
b
=
N
+
1
-
a
↔
N
+
1
-
b
∈
ℤ
∧
N
+
1
-
b
≤
N
∧
b
=
N
+
1
-
N
+
1
-
b
69
68
ad2antll
⊢
N
∈
ℤ
∧
b
∈
ℤ
∧
1
≤
b
∧
a
=
N
+
1
-
b
→
a
∈
ℤ
∧
a
≤
N
∧
b
=
N
+
1
-
a
↔
N
+
1
-
b
∈
ℤ
∧
N
+
1
-
b
≤
N
∧
b
=
N
+
1
-
N
+
1
-
b
70
62
69
mpbird
⊢
N
∈
ℤ
∧
b
∈
ℤ
∧
1
≤
b
∧
a
=
N
+
1
-
b
→
a
∈
ℤ
∧
a
≤
N
∧
b
=
N
+
1
-
a
71
40
70
impbida
⊢
N
∈
ℤ
→
a
∈
ℤ
∧
a
≤
N
∧
b
=
N
+
1
-
a
↔
b
∈
ℤ
∧
1
≤
b
∧
a
=
N
+
1
-
b
72
ellz1
⊢
N
∈
ℤ
→
a
∈
ℤ
∖
ℤ
≥
N
+
1
↔
a
∈
ℤ
∧
a
≤
N
73
72
anbi1d
⊢
N
∈
ℤ
→
a
∈
ℤ
∖
ℤ
≥
N
+
1
∧
b
=
N
+
1
-
a
↔
a
∈
ℤ
∧
a
≤
N
∧
b
=
N
+
1
-
a
74
elnnz1
⊢
b
∈
ℕ
↔
b
∈
ℤ
∧
1
≤
b
75
74
a1i
⊢
N
∈
ℤ
→
b
∈
ℕ
↔
b
∈
ℤ
∧
1
≤
b
76
75
anbi1d
⊢
N
∈
ℤ
→
b
∈
ℕ
∧
a
=
N
+
1
-
b
↔
b
∈
ℤ
∧
1
≤
b
∧
a
=
N
+
1
-
b
77
71
73
76
3bitr4d
⊢
N
∈
ℤ
→
a
∈
ℤ
∖
ℤ
≥
N
+
1
∧
b
=
N
+
1
-
a
↔
b
∈
ℕ
∧
a
=
N
+
1
-
b
78
3
5
7
9
77
en2d
⊢
N
∈
ℤ
→
ℤ
∖
ℤ
≥
N
+
1
≈
ℕ
79
nnenom
ω
⊢
ℕ
≈
ω
80
entr
ω
ω
⊢
ℤ
∖
ℤ
≥
N
+
1
≈
ℕ
∧
ℕ
≈
ω
→
ℤ
∖
ℤ
≥
N
+
1
≈
ω
81
78
79
80
sylancl
ω
⊢
N
∈
ℤ
→
ℤ
∖
ℤ
≥
N
+
1
≈
ω