nprofile1qy2hwumn8ghj7un9d3shjtnyd968gmewwp6kyqpq5m29pdfzjm5zj3hhjs7zm329cwlrxwjr4mvl607vw0yxd8kdrjmscms7d2 (nprofile…s7d2) - You're making me think I was mixed up. (I wrote that stuff a long time ago and haven't thought about it in years.) The proof-theoretic ordinal of PRA is \(\omega^\omega
\) but it sounds like PRA is only supposed to be able to define primitive recursive functions, hence not the Ackermann function.
nprofile1qy2hwumn8ghj7un9d3shjtnyd968gmewwp6kyqpqez3yya8tpgge7lk4jq2zxz0cj3d2mcgev9mffd4ec7tfy84hre4skst6k2 (nprofile…t6k2) nprofile1qy2hwumn8ghj7un9d3shjtnyd968gmewwp6kyqpqw9kjj2cu9q6vtvg5m9j9szkl0z9fvcxfxc93aeamrvgl9fjtjjuswyz2n3 (nprofile…z2n3)
John Carlos Baez
npub17u…8pd6m
2026-01-31 17:45:45 UTC
in reply to nevent1q…n5n3
Author Public Key
npub17u6xav5rjq4d48fpcyy6j05rz2xelp7clnl8ptvpnval9tvmectqp8pd6mPublished at
2026-01-31 17:45:45 UTCEvent JSON
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