English
For any natural m and i, j ∈ Fin n, image of Ico i j under natAdd m equals Ico (natAdd m i) (natAdd m j).
Русский
Для любого натурального m и i, j ∈ Fin n образ Ico i j под natAdd m равен Ico (natAdd m i) (natAdd m j).
LaTeX
$$$$(\\mathrm{Ico}\\ i\\ j).\\operatorname{image}(\\mathrm{natAdd}\\ m) = \\mathrm{Ico}(\\mathrm{natAdd}\\ m\,i, \\mathrm{natAdd}\\ m\,j)$$$$
Lean4
@[simp]
theorem finsetImage_natAdd_Ico (m) (i j : Fin n) : (Ico i j).image (natAdd m) = Ico (natAdd m i) (natAdd m j) := by
simp [← coe_inj]