Metamath Proof Explorer


Theorem fndmfifsupp

Description: A function with a finite domain is always finitely supported. (Contributed by AV, 25-May-2019)

Ref Expression
Hypotheses fndmfisuppfi.f φ F Fn D
fndmfisuppfi.d φ D Fin
fndmfisuppfi.z φ Z V
Assertion fndmfifsupp φ finSupp Z F

Proof

Step Hyp Ref Expression
1 fndmfisuppfi.f φ F Fn D
2 fndmfisuppfi.d φ D Fin
3 fndmfisuppfi.z φ Z V
4 dffn3 F Fn D F : D ran F
5 1 4 sylib φ F : D ran F
6 5 2 3 fdmfifsupp φ finSupp Z F