Metamath Proof Explorer


Theorem reno

Description: A surreal real is a surreal number. (Contributed by Scott Fenton, 19-Feb-2026)

Ref Expression
Assertion reno ⊢ A ∈ ℝ s → A ∈ No

Proof

Step Hyp Ref Expression
1 elreno ⊢ A ∈ ℝ s ↔ A ∈ No ∧ ∃ n ∈ ℕ s + s ⁡ n < s A ∧ A < s n ∧ A = x | ∃ n ∈ ℕ s x = A - s 1 s / su n | s x | ∃ n ∈ ℕ s x = A + s 1 s / su n
2 1 simplbi ⊢ A ∈ ℝ s → A ∈ No