( Countable ∧ $T_1$ ) ⇒ $G_\delta$ space

Every subset of $X$ is an $F_\sigma$, as it is a countable union of singletons.

• Converse
• References

The converse ( $G_\delta$ space ⇒ ( Countable ∧ $T_1$ )) cannot be proven or disproven from other known theorems