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Algebraic numbers
aannen
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Liouville's approximation theorem
Metamath Proof Explorer
Ascii
Unicode
Theorem
aannen
Description:
The algebraic numbers are countable.
(Contributed by
Stefan O'Rear
, 16-Nov-2014)
Ref
Expression
Assertion
aannen
⊢
𝔸
≈
ℕ
Proof
Step
Hyp
Ref
Expression
1
eqid
⊢
a
∈
ℕ
0
⟼
b
∈
ℂ
|
∃
c
∈
d
∈
Poly
⁡
ℤ
|
d
≠
0
𝑝
∧
deg
⁡
d
≤
a
∧
∀
e
∈
ℕ
0
coeff
⁡
d
⁡
e
≤
a
c
⁡
b
=
0
=
a
∈
ℕ
0
⟼
b
∈
ℂ
|
∃
c
∈
d
∈
Poly
⁡
ℤ
|
d
≠
0
𝑝
∧
deg
⁡
d
≤
a
∧
∀
e
∈
ℕ
0
coeff
⁡
d
⁡
e
≤
a
c
⁡
b
=
0
2
1
aannenlem3
⊢
𝔸
≈
ℕ