Metamath Proof Explorer


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