Cardinality of continuous real functions

ID: cardinality-of-continuous-real-functions

The set of continuous functions has cardinality . Constant functions provide the lower bound. Restriction to the dense set is injective, since continuity determines a function from its values there. Real sequences have cardinality , by encoding a sequence using its countably many rational lower cuts. Restriction therefore supplies the upper bound and Cantor-Schröder-Bernstein gives equality.

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