Harmonic class 5. Not a very common term, but it does see uses occasionally. FloraC (talk) 12:51, 21 April 2025 (UTC)
Yeah, I still use the term. In my usage "p-limit" refers to all primes up to and including p, while HCp refers to only intervals in the p-limit that contain p itself. Lériendil (talk) 13:18, 21 April 2025 (UTC)