Denumerable Set

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denumerable set

[də′nüm·rə·bəl ′set]
A set which may be put in one-to-one correspondence with the positive integers. Also known as countably infinite set.

Denumerable Set


(or countably infinite set), an infinite set whose elements can be indexed by the natural numbers—that is, a one-to-one correspondence can be established between the set of all natural numbers. As G. Cantor demonstrated, the set of all rational numbers and even the set of all algebraic numbers are denumerable, but the set of all real numbers is nondenumerable. Every infinite set contains a denumerable subset. The union of a finite or denumerable set of denumerable sets is also a denumerable set.

References in periodicals archive ?
Let G acting on a denumerable set E and R be a relational structure such that AutR = [bar.
It is clear that the model M (the family M) includes absolutely denumerable sets.