Metamath Proof Explorer


Theorem mucl

Description: Closure of the MΓΆbius function. (Contributed by Mario Carneiro, 22-Sep-2014)

Ref Expression
Assertion mucl ( 𝐴 ∈ β„• β†’ ( ΞΌ β€˜ 𝐴 ) ∈ β„€ )

Proof

Step Hyp Ref Expression
1 muf ⊒ ΞΌ : β„• ⟢ β„€
2 1 ffvelcdmi ⊒ ( 𝐴 ∈ β„• β†’ ( ΞΌ β€˜ 𝐴 ) ∈ β„€ )