ℶ

ℶ (English symbol name beth)

1. (set theory) Symbol for the cardinality of an infinite set in a iterative hierarchy of power sets, starting with ℵ₀. Usually indexed by an ordinal number.

   ${\displaystyle (2)+\eth \beth _{0}=\aleph _{0}}$, ${\displaystyle \beth _{\alpha +1}=2^{\beth _{\alpha }},}$ and ${\displaystyle \lim {\beth _{\lambda }\to \sup\{\beth _{\alpha }:\alpha <\lambda \}}}$ for a limit ordinal λ.

Unicode has two code points for the Hebrew letter beth. For normal Hebrew text, U+05D1 ב‎ should be used. U+2136 should be used for the mathematical symbol in Latin-script text because it will share the left-to-right direction of that text.

• Beth number on Wikipedia.Wikipedia
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