Metamath Proof Explorer


Theorem volsuplem

Description: Lemma for volsup . (Contributed by Mario Carneiro, 4-Jul-2014)

Ref Expression
Assertion volsuplem ⊢ ∀ n ∈ ℕ F ⁡ n ⊆ F ⁡ n + 1 ∧ A ∈ ℕ ∧ B ∈ ℤ ≥ A → F ⁡ A ⊆ F ⁡ B

Proof

Step Hyp Ref Expression
1 fveq2 ⊢ x = A → F ⁡ x = F ⁡ A
2 1 sseq2d ⊢ x = A → F ⁡ A ⊆ F ⁡ x ↔ F ⁡ A ⊆ F ⁡ A
3 2 imbi2d ⊢ x = A → ∀ n ∈ ℕ F ⁡ n ⊆ F ⁡ n + 1 ∧ A ∈ ℕ → F ⁡ A ⊆ F ⁡ x ↔ ∀ n ∈ ℕ F ⁡ n ⊆ F ⁡ n + 1 ∧ A ∈ ℕ → F ⁡ A ⊆ F ⁡ A
4 fveq2 ⊢ x = k → F ⁡ x = F ⁡ k
5 4 sseq2d ⊢ x = k → F ⁡ A ⊆ F ⁡ x ↔ F ⁡ A ⊆ F ⁡ k
6 5 imbi2d ⊢ x = k → ∀ n ∈ ℕ F ⁡ n ⊆ F ⁡ n + 1 ∧ A ∈ ℕ → F ⁡ A ⊆ F ⁡ x ↔ ∀ n ∈ ℕ F ⁡ n ⊆ F ⁡ n + 1 ∧ A ∈ ℕ → F ⁡ A ⊆ F ⁡ k
7 fveq2 ⊢ x = k + 1 → F ⁡ x = F ⁡ k + 1
8 7 sseq2d ⊢ x = k + 1 → F ⁡ A ⊆ F ⁡ x ↔ F ⁡ A ⊆ F ⁡ k + 1
9 8 imbi2d ⊢ x = k + 1 → ∀ n ∈ ℕ F ⁡ n ⊆ F ⁡ n + 1 ∧ A ∈ ℕ → F ⁡ A ⊆ F ⁡ x ↔ ∀ n ∈ ℕ F ⁡ n ⊆ F ⁡ n + 1 ∧ A ∈ ℕ → F ⁡ A ⊆ F ⁡ k + 1
10 fveq2 ⊢ x = B → F ⁡ x = F ⁡ B
11 10 sseq2d ⊢ x = B → F ⁡ A ⊆ F ⁡ x ↔ F ⁡ A ⊆ F ⁡ B
12 11 imbi2d ⊢ x = B → ∀ n ∈ ℕ F ⁡ n ⊆ F ⁡ n + 1 ∧ A ∈ ℕ → F ⁡ A ⊆ F ⁡ x ↔ ∀ n ∈ ℕ F ⁡ n ⊆ F ⁡ n + 1 ∧ A ∈ ℕ → F ⁡ A ⊆ F ⁡ B
13 ssid ⊢ F ⁡ A ⊆ F ⁡ A
14 13 2a1i ⊢ A ∈ ℤ → ∀ n ∈ ℕ F ⁡ n ⊆ F ⁡ n + 1 ∧ A ∈ ℕ → F ⁡ A ⊆ F ⁡ A
15 eluznn ⊢ A ∈ ℕ ∧ k ∈ ℤ ≥ A → k ∈ ℕ
16 fveq2 ⊢ n = k → F ⁡ n = F ⁡ k
17 fvoveq1 ⊢ n = k → F ⁡ n + 1 = F ⁡ k + 1
18 16 17 sseq12d ⊢ n = k → F ⁡ n ⊆ F ⁡ n + 1 ↔ F ⁡ k ⊆ F ⁡ k + 1
19 18 rspccva ⊢ ∀ n ∈ ℕ F ⁡ n ⊆ F ⁡ n + 1 ∧ k ∈ ℕ → F ⁡ k ⊆ F ⁡ k + 1
20 15 19 sylan2 ⊢ ∀ n ∈ ℕ F ⁡ n ⊆ F ⁡ n + 1 ∧ A ∈ ℕ ∧ k ∈ ℤ ≥ A → F ⁡ k ⊆ F ⁡ k + 1
21 20 anassrs ⊢ ∀ n ∈ ℕ F ⁡ n ⊆ F ⁡ n + 1 ∧ A ∈ ℕ ∧ k ∈ ℤ ≥ A → F ⁡ k ⊆ F ⁡ k + 1
22 sstr2 ⊢ F ⁡ A ⊆ F ⁡ k → F ⁡ k ⊆ F ⁡ k + 1 → F ⁡ A ⊆ F ⁡ k + 1
23 21 22 syl5com ⊢ ∀ n ∈ ℕ F ⁡ n ⊆ F ⁡ n + 1 ∧ A ∈ ℕ ∧ k ∈ ℤ ≥ A → F ⁡ A ⊆ F ⁡ k → F ⁡ A ⊆ F ⁡ k + 1
24 23 expcom ⊢ k ∈ ℤ ≥ A → ∀ n ∈ ℕ F ⁡ n ⊆ F ⁡ n + 1 ∧ A ∈ ℕ → F ⁡ A ⊆ F ⁡ k → F ⁡ A ⊆ F ⁡ k + 1
25 24 a2d ⊢ k ∈ ℤ ≥ A → ∀ n ∈ ℕ F ⁡ n ⊆ F ⁡ n + 1 ∧ A ∈ ℕ → F ⁡ A ⊆ F ⁡ k → ∀ n ∈ ℕ F ⁡ n ⊆ F ⁡ n + 1 ∧ A ∈ ℕ → F ⁡ A ⊆ F ⁡ k + 1
26 3 6 9 12 14 25 uzind4 ⊢ B ∈ ℤ ≥ A → ∀ n ∈ ℕ F ⁡ n ⊆ F ⁡ n + 1 ∧ A ∈ ℕ → F ⁡ A ⊆ F ⁡ B
27 26 com12 ⊢ ∀ n ∈ ℕ F ⁡ n ⊆ F ⁡ n + 1 ∧ A ∈ ℕ → B ∈ ℤ ≥ A → F ⁡ A ⊆ F ⁡ B
28 27 impr ⊢ ∀ n ∈ ℕ F ⁡ n ⊆ F ⁡ n + 1 ∧ A ∈ ℕ ∧ B ∈ ℤ ≥ A → F ⁡ A ⊆ F ⁡ B