Metamath Proof Explorer


Theorem wrdfsupp

Description: A word has finite support. (Contributed by Thierry Arnoux, 27-May-2025)

Ref Expression
Hypotheses wrdfsupp.1 ⊢ ( 𝜑 → 𝑍 ∈ 𝑉 )
wrdfsupp.2 ⊢ ( 𝜑 → 𝑊 ∈ Word 𝑆 )
Assertion wrdfsupp ( 𝜑 → 𝑊 finSupp 𝑍 )

Proof

Step Hyp Ref Expression
1 wrdfsupp.1 ⊢ ( 𝜑 → 𝑍 ∈ 𝑉 )
2 wrdfsupp.2 ⊢ ( 𝜑 → 𝑊 ∈ Word 𝑆 )
3 eqidd ⊢ ( 𝜑 → ( ♯ ‘ 𝑊 ) = ( ♯ ‘ 𝑊 ) )
4 3 2 wrdfd ⊢ ( 𝜑 → 𝑊 : ( 0 ..^ ( ♯ ‘ 𝑊 ) ) ⟶ 𝑆 )
5 fzofi ⊢ ( 0 ..^ ( ♯ ‘ 𝑊 ) ) ∈ Fin
6 5 a1i ⊢ ( 𝜑 → ( 0 ..^ ( ♯ ‘ 𝑊 ) ) ∈ Fin )
7 4 6 1 fdmfifsupp ⊢ ( 𝜑 → 𝑊 finSupp 𝑍 )