English
A Fin(n)-graded order on α is also a Nat-graded order on α.
Русский
Упорядочение α с градацией Fin(n) также можно рассматривать как Nat-градиент на α.
LaTeX
$$$[GradeOrder (Fin n) α] \\Rightarrow [GradeOrder \\mathbb{N} α]$$$
Lean4
/-- A `Fin n`-graded order is also `ℕ`-graded. We do not mark this an instance because `n` is not
inferable. -/
abbrev finToNat (n : ℕ) [GradeOrder (Fin n) α] : GradeOrder ℕ α :=
(GradeOrder.liftLeft (_ : Fin n → ℕ) Fin.val_strictMono) fun _ _ => CovBy.coe_fin