Description: The empty set is a finitely supported function. (Contributed by AV, 19-Jul-2019)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | 0fsupp | ⊢ ( 𝑍 ∈ 𝑉 → ∅ finSupp 𝑍 ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | supp0 | ⊢ ( 𝑍 ∈ 𝑉 → ( ∅ supp 𝑍 ) = ∅ ) | |
| 2 | 0fi | ⊢ ∅ ∈ Fin | |
| 3 | 1 2 | eqeltrdi | ⊢ ( 𝑍 ∈ 𝑉 → ( ∅ supp 𝑍 ) ∈ Fin ) |
| 4 | fun0 | ⊢ Fun ∅ | |
| 5 | 0ex | ⊢ ∅ ∈ V | |
| 6 | funisfsupp | ⊢ ( ( Fun ∅ ∧ ∅ ∈ V ∧ 𝑍 ∈ 𝑉 ) → ( ∅ finSupp 𝑍 ↔ ( ∅ supp 𝑍 ) ∈ Fin ) ) | |
| 7 | 4 5 6 | mp3an12 | ⊢ ( 𝑍 ∈ 𝑉 → ( ∅ finSupp 𝑍 ↔ ( ∅ supp 𝑍 ) ∈ Fin ) ) |
| 8 | 3 7 | mpbird | ⊢ ( 𝑍 ∈ 𝑉 → ∅ finSupp 𝑍 ) |