# fast-growing hierarchy

> ordinal-indexed family of rapidly increasing functions: ℕ→ℕ

**Wikidata**: [Q3138738](https://www.wikidata.org/wiki/Q3138738)  
**Wikipedia**: [English](https://en.wikipedia.org/wiki/Fast-growing_hierarchy)  
**Source**: https://4ort.xyz/entity/fast-growing-hierarchy