Large Countable Ordinals (Part 1)
by John C. Baez · Azimuth (blog)
Unique free resource for going beyond textbook ordinal arithmetic into ordinal notations (epsilon-nought, Veblen functions) relevant to proof theory. First of John Baez's three-part Azimuth blog series on countable ordinals. Covers omega, ordinal addition, multiplication and exponentiation, Cantor normal form and epsilon-nought; Parts 2–3 continue through the Veblen hierarchy to the Feferman–Schütte and Veblen ordinals.
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