User blog comment:Deedlit11/Extending the fast-growing hierarchy to nonrecursive ordinals/@comment-25418284-20130325203802/@comment-25418284-20130325211916

That's what I meant :P \(\Phi(0, \mathcal{O}(n)) \equiv \omega_{\mathcal{O}(n)}^\text{CK}\) as defined in the article.