Such sets are countably infinite or countable.
A discrete probability distribution is one where the random variable can only assume a finite, or countably infinite, number of values.
Una distribución de probabilidad discreta es aquella en la que la variable aleatoria solo puede asumir un número finito, o contablemente infinito, de valores.
The set X will be non-measurable for any rotation-invariant countably additive probability measure on S: if X has zero measure, countable additivity would imply that the whole circle has zero measure.
El conjunto X será no medible para cualquier medida de probabilidad numerablemente aditiva y rotacionalmente invariante sobre S: si X tiene medida cero, la aditividad numerable implicaría que la circunferencia completa tiene medida cero.
An easy example of a non-metacompact space (but a countably metacompact space) is the Moore plane.
Un ejemplo sencillo de un espacio no metacompacto (pero sí numerablemente metacompacto) es el plano de Moore.
However, there could be countably many homoclinic orbits connecting one fixed point.
ZF + ACω suffices to prove that the union of countably many countable sets is countable.
ZF + ACω es suficiente para probar que la unión de una cantidad numerable de conjuntos numerables es numerable.
Even if B is uncountable, Bessel's inequality guarantees that the expression is well-defined and consists only of countably many nonzero terms.
Incluso si B no es numerable, solo contablemente muchos términos en esta suma serán diferentes a cero, y la expresión está por lo tanto bien definida.
A space is σ-compact if it is the union of countably many compact subsets.
Un espacio es σ-compacto si es la Unión de subconjuntos compactos contablemente muchos.
The theorem states that a topological space X {\displaystyle X} is metrizable if and only if it is regular, Hausdorff and has a countably locally finite (i.e., σ-locally finite) basis.
El teorema afirma que un espacio topológico X {\displaystyle X} es metrizable si y solo si es regular, Hausdorff y tiene una base numerablemente localmente finita (esto es, σ-localmente finita).
compact if it is the union of countably many compact subsets. Paracompact.
Un espacio es compacto si es la Unión de subconjuntos compactos contablemente muchos.
There are only countably many finite sequences, so also there are only countably many finite subsets.
A countably infinite set is one that can be enumerated.
The cardinality of a countably infinite set is denoted as aleph-zero.