Metamath Proof Explorer


Theorem fzp1elp1

Description: Add one to an element of a finite set of integers. (Contributed by Jeff Madsen, 6-Jun-2010) (Revised by Mario Carneiro, 28-Apr-2015)

Ref Expression
Assertion fzp1elp1 ⊢ K ∈ M … N → K + 1 ∈ M … N + 1

Proof

Step Hyp Ref Expression
1 elfzuz ⊢ K ∈ M … N → K ∈ ℤ ≥ M
2 peano2uz ⊢ K ∈ ℤ ≥ M → K + 1 ∈ ℤ ≥ M
3 1 2 syl ⊢ K ∈ M … N → K + 1 ∈ ℤ ≥ M
4 elfzuz3 ⊢ K ∈ M … N → N ∈ ℤ ≥ K
5 eluzp1p1 ⊢ N ∈ ℤ ≥ K → N + 1 ∈ ℤ ≥ K + 1
6 4 5 syl ⊢ K ∈ M … N → N + 1 ∈ ℤ ≥ K + 1
7 elfzuzb ⊢ K + 1 ∈ M … N + 1 ↔ K + 1 ∈ ℤ ≥ M ∧ N + 1 ∈ ℤ ≥ K + 1
8 3 6 7 sylanbrc ⊢ K ∈ M … N → K + 1 ∈ M … N + 1