Metamath Proof Explorer


Theorem fzval2

Description: An alternative way of expressing a finite set of sequential integers. (Contributed by Mario Carneiro, 3-Nov-2013)

Ref Expression
Assertion fzval2 ⊢ M ∈ ℤ ∧ N ∈ ℤ → M … N = M N ∩ ℤ

Proof

Step Hyp Ref Expression
1 fzval ⊢ M ∈ ℤ ∧ N ∈ ℤ → M … N = k ∈ ℤ | M ≤ k ∧ k ≤ N
2 zssre ⊢ ℤ ⊆ ℝ
3 ressxr ⊢ ℝ ⊆ ℝ *
4 2 3 sstri ⊢ ℤ ⊆ ℝ *
5 4 sseli ⊢ M ∈ ℤ → M ∈ ℝ *
6 4 sseli ⊢ N ∈ ℤ → N ∈ ℝ *
7 iccval ⊢ M ∈ ℝ * ∧ N ∈ ℝ * → M N = k ∈ ℝ * | M ≤ k ∧ k ≤ N
8 5 6 7 syl2an ⊢ M ∈ ℤ ∧ N ∈ ℤ → M N = k ∈ ℝ * | M ≤ k ∧ k ≤ N
9 8 ineq1d ⊢ M ∈ ℤ ∧ N ∈ ℤ → M N ∩ ℤ = k ∈ ℝ * | M ≤ k ∧ k ≤ N ∩ ℤ
10 inrab2 ⊢ k ∈ ℝ * | M ≤ k ∧ k ≤ N ∩ ℤ = k ∈ ℝ * ∩ ℤ | M ≤ k ∧ k ≤ N
11 sseqin2 ⊢ ℤ ⊆ ℝ * ↔ ℝ * ∩ ℤ = ℤ
12 4 11 mpbi ⊢ ℝ * ∩ ℤ = ℤ
13 12 rabeqi ⊢ k ∈ ℝ * ∩ ℤ | M ≤ k ∧ k ≤ N = k ∈ ℤ | M ≤ k ∧ k ≤ N
14 10 13 eqtri ⊢ k ∈ ℝ * | M ≤ k ∧ k ≤ N ∩ ℤ = k ∈ ℤ | M ≤ k ∧ k ≤ N
15 9 14 eqtr2di ⊢ M ∈ ℤ ∧ N ∈ ℤ → k ∈ ℤ | M ≤ k ∧ k ≤ N = M N ∩ ℤ
16 1 15 eqtrd ⊢ M ∈ ℤ ∧ N ∈ ℤ → M … N = M N ∩ ℤ