countable: said of a set, either finite or infinite, whose elements can be put in one-to-one correspondence with the natural integers
Origin of denumerablede- + numerable
Capable of being put into one-to-one correspondence with the positive integers; countable.
Origin of denumerableFrom denumerate to count from Late Latin dēnumerāre dēnumerāt- alteration of Latin dīnumerāre dī-, dis- dis- numerāre to number ; see numerate .
- (mathematics) Capable of being assigned numbers from the natural numbers. Especially applied to sets where finite sets and sets that have a one-to-one mapping to the natural numbers are called denumerable.
- The empty set is denumerable because it is finite; the rational numbers are, surprisingly, denumerable because every possible fraction can be assigned a number.