Metamath Proof Explorer


Theorem 0nelfz1

Description: 0 is not an element of a finite interval of integers starting at 1. (Contributed by AV, 27-Aug-2020)

Ref Expression
Assertion 0nelfz1 ⊢ 0 ∉ 1 … N

Proof

Step Hyp Ref Expression
1 0lt1 ⊢ 0 < 1
2 0re ⊢ 0 ∈ ℝ
3 1re ⊢ 1 ∈ ℝ
4 2 3 ltnlei ⊢ 0 < 1 ↔ ¬ 1 ≤ 0
5 1 4 mpbi ⊢ ¬ 1 ≤ 0
6 5 intnanr ⊢ ¬ 1 ≤ 0 ∧ 0 ≤ N
7 6 intnan ⊢ ¬ 1 ∈ ℤ ∧ N ∈ ℤ ∧ 0 ∈ ℤ ∧ 1 ≤ 0 ∧ 0 ≤ N
8 df-nel ⊢ 0 ∉ 1 … N ↔ ¬ 0 ∈ 1 … N
9 elfz2 ⊢ 0 ∈ 1 … N ↔ 1 ∈ ℤ ∧ N ∈ ℤ ∧ 0 ∈ ℤ ∧ 1 ≤ 0 ∧ 0 ≤ N
10 8 9 xchbinx ⊢ 0 ∉ 1 … N ↔ ¬ 1 ∈ ℤ ∧ N ∈ ℤ ∧ 0 ∈ ℤ ∧ 1 ≤ 0 ∧ 0 ≤ N
11 7 10 mpbir ⊢ 0 ∉ 1 … N