English
For any v, deg(ofFn n v) < n.
Русский
Для любого v, deg(ofFn n v) < n.
LaTeX
$$$\deg(\operatorname{ofFn}(n)\, v) < n.$$$
Lean4
/-- `ofFn n v` has `degree` smaller than `n`. -/
theorem ofFn_degree_lt {n : ℕ} (v : Fin n → R) : (ofFn n v).degree < n :=
by
by_cases h : ofFn n v = 0
· simp only [h, degree_zero]
exact Batteries.compareOfLessAndEq_eq_lt.mp rfl
·
exact
(natDegree_lt_iff_degree_lt h).mp <| ofFn_natDegree_lt (Nat.one_le_iff_ne_zero.mpr <| ne_zero_of_ofFn_ne_zero h) _