English
For any Fin n and m, the image of the half-open interval Ico i j under the map castAdd m is Ico (castAdd m i) (castAdd m j).
Русский
Для любых i, j ∈ Fin n и m ∈ ℕ образ Ico i j под отображением castAdd m равен Ico (castAdd m i) (castAdd m j).
LaTeX
$$$ (\mathrm{Finset}.Ico\, i\, j).image (\mathrm{Fin.castAdd}\, m) = \mathrm{Finset}.Ico\ (\mathrm{Fin.castAdd}\, m\, i)\ (\mathrm{Fin.castAdd}\, m\, j) $$$
Lean4
@[simp]
theorem finsetImage_castAdd_Ico (m) (i j : Fin n) : (Ico i j).image (castAdd m) = Ico (castAdd m i) (castAdd m j) :=
finsetImage_castLE_Ico ..