Metamath Proof Explorer


Theorem fsuppmapnn0fz

Description: If a function over the nonnegative integers is finitely supported, then there is an upper bound for a finite set of sequential integers containing the support of the function. (Contributed by AV, 30-Sep-2019) (Proof shortened by AV, 6-Oct-2019)

Ref Expression
Assertion fsuppmapnn0fz ⊢ F ∈ R ℕ 0 ∧ Z ∈ V → finSupp Z⁡ F → ∃ m ∈ ℕ 0 F supp Z ⊆ 0 … m

Proof

Step Hyp Ref Expression
1 fsuppmapnn0ub ⊢ F ∈ R ℕ 0 ∧ Z ∈ V → finSupp Z⁡ F → ∃ m ∈ ℕ 0 ∀ x ∈ ℕ 0 m < x → F ⁡ x = Z
2 simpllr ⊢ F ∈ R ℕ 0 ∧ Z ∈ V ∧ m ∈ ℕ 0 ∧ ∀ x ∈ ℕ 0 m < x → F ⁡ x = Z → Z ∈ V
3 simplll ⊢ F ∈ R ℕ 0 ∧ Z ∈ V ∧ m ∈ ℕ 0 ∧ ∀ x ∈ ℕ 0 m < x → F ⁡ x = Z → F ∈ R ℕ 0
4 simplr ⊢ F ∈ R ℕ 0 ∧ Z ∈ V ∧ m ∈ ℕ 0 ∧ ∀ x ∈ ℕ 0 m < x → F ⁡ x = Z → m ∈ ℕ 0
5 simpr ⊢ F ∈ R ℕ 0 ∧ Z ∈ V ∧ m ∈ ℕ 0 ∧ ∀ x ∈ ℕ 0 m < x → F ⁡ x = Z → ∀ x ∈ ℕ 0 m < x → F ⁡ x = Z
6 2 3 4 5 suppssfz ⊢ F ∈ R ℕ 0 ∧ Z ∈ V ∧ m ∈ ℕ 0 ∧ ∀ x ∈ ℕ 0 m < x → F ⁡ x = Z → F supp Z ⊆ 0 … m
7 6 ex ⊢ F ∈ R ℕ 0 ∧ Z ∈ V ∧ m ∈ ℕ 0 → ∀ x ∈ ℕ 0 m < x → F ⁡ x = Z → F supp Z ⊆ 0 … m
8 7 reximdva ⊢ F ∈ R ℕ 0 ∧ Z ∈ V → ∃ m ∈ ℕ 0 ∀ x ∈ ℕ 0 m < x → F ⁡ x = Z → ∃ m ∈ ℕ 0 F supp Z ⊆ 0 … m
9 1 8 syld ⊢ F ∈ R ℕ 0 ∧ Z ∈ V → finSupp Z⁡ F → ∃ m ∈ ℕ 0 F supp Z ⊆ 0 … m