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Rayo(10^100)
Rayo's Number
DEFINITION
The largest number expressible in no more than a googol symbols in the language of first-order set theory.
Transcends all computable and most definable functions. No notation system can express it.
HIERARCHY
Sits at the apex of named large numbers — defined via the full expressiveness of set-theoretic language.
COMPARISON
Makes Graham's number, TREE(3), and even the Busy Beaver function look like zero.
The largest named number · rotates daily