We prove an isomorphism theorem between the canonical denotation systems for large natural numbers and large countable ordinal numbers. linking two fundamental concepts in Proof Theory. The first one is fast-growing hierarchies. These are sequences of functions on $\mathbb {N}$ obtained through processes such as the ones that yield multiplication from addition. https://www.hindigyanvishv.com/hot-find-Facia-Installation-Kit-Suits-Holden-Commodore-VE-Series-2-FP9550BK-Black-top-mega/