English
For all m ∈ ℕ and i, j ∈ Fin(n), the image of uIoc(i, j) under x ↦ x + m is uIoc(i + m, j + m).
Русский
Для всех m ∈ ℕ и i, j ∈ Fin(n) образ uIoc(i, j) при сдвиге на m равен uIoc(i + m, j + m).
LaTeX
$$$$ \\mathrm{Set.image}(\\\\mathrm{Fin.natAdd}(m))(\\\\mathrm{Set.uIoc}(i,j)) = \\\\mathrm{Set.uIoc}(\\\\mathrm{Fin.natAdd}(m)i, \\\\mathrm{Fin.natAdd}(m)j). $$$$
Lean4
@[simp]
theorem image_addNat_uIoc (m) (i j : Fin n) : (addNat · m) '' uIoc i j = uIoc (i.addNat m) (j.addNat m) := by
simp [uIoc, ← (strictMono_addNat m).monotone.map_max, ← (strictMono_addNat m).monotone.map_min]