Theorem onno

Description: A surreal ordinal is a surreal. (Contributed by Scott Fenton, 18-Mar-2025)

	Ref	Expression
Assertion	onno	$$⊢A\in {On}_s\to A\in \mathrm{No}$$

Proof

Step	Hyp	Ref	Expression
1		onssno	$$⊢{On}_s\subseteq \mathrm{No}$$
2	1	sseli	$$⊢A\in {On}_s\to A\in \mathrm{No}$$