Metamath Proof Explorer


Theorem flodddiv4lt

Description: The floor of an odd number divided by 4 is less than the odd number divided by 4. (Contributed by AV, 4-Jul-2021)

Ref Expression
Assertion flodddiv4lt ⊢ N ∈ ℤ ∧ ¬ 2 ∥ N → N 4 < N 4

Proof

Step Hyp Ref Expression
1 simpl ⊢ N ∈ ℤ ∧ ¬ 2 ∥ N → N ∈ ℤ
2 4z ⊢ 4 ∈ ℤ
3 4ne0 ⊢ 4 ≠ 0
4 2 3 pm3.2i ⊢ 4 ∈ ℤ ∧ 4 ≠ 0
5 4 a1i ⊢ N ∈ ℤ ∧ ¬ 2 ∥ N → 4 ∈ ℤ ∧ 4 ≠ 0
6 4dvdseven ⊢ 4 ∥ N → 2 ∥ N
7 6 con3i ⊢ ¬ 2 ∥ N → ¬ 4 ∥ N
8 7 adantl ⊢ N ∈ ℤ ∧ ¬ 2 ∥ N → ¬ 4 ∥ N
9 fldivndvdslt ⊢ N ∈ ℤ ∧ 4 ∈ ℤ ∧ 4 ≠ 0 ∧ ¬ 4 ∥ N → N 4 < N 4
10 1 5 8 9 syl3anc ⊢ N ∈ ℤ ∧ ¬ 2 ∥ N → N 4 < N 4