Metamath Proof Explorer


Theorem climresd

Description: A function restricted to upper integers converges iff the original function converges. (Contributed by Glauco Siliprandi, 23-Apr-2023)

Ref Expression
Hypotheses climresd.1
|- ( ph -> M e. ZZ )
climresd.2
|- ( ph -> F e. V )
Assertion climresd
|- ( ph -> ( ( F |` ( ZZ>= ` M ) ) ~~> A <-> F ~~> A ) )

Proof

Step Hyp Ref Expression
1 climresd.1
 |-  ( ph -> M e. ZZ )
2 climresd.2
 |-  ( ph -> F e. V )
3 climres
 |-  ( ( M e. ZZ /\ F e. V ) -> ( ( F |` ( ZZ>= ` M ) ) ~~> A <-> F ~~> A ) )
4 1 2 3 syl2anc
 |-  ( ph -> ( ( F |` ( ZZ>= ` M ) ) ~~> A <-> F ~~> A ) )