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Erdös cardinal

In mathematical logic, a cardinal number κ, which the least cardinal such that for every function f: κ < ω → {0, 1} there is a set of order type α that is homogeneous for f, is called an α-Erdős cardinal.

It is consistent with V=L that for every countable ordinal α, there is an α-Erdős cardinal. However, existence of an &omega1-Erdős cardinal implies the existence of zero sharp.