English
The map finSuccAboveEquiv(p) sends i to the pair (p.succAbove(i), p.succAbove_ne(i)).
Русский
Отображение finSuccAboveEquiv(p) отправляет i в пару (p.succAbove(i), p.succAbove_ne(i)).
LaTeX
$$$$ \\forall p \\in \\mathrm{Fin}(n+1), \\forall i \\in \\mathrm{Fin}(n), \\\\n\\; \\mathrm{finSuccAboveEquiv}(p)(i) = \\langle p.succAbove(i), p.succAbove\\_ne(i) \\rangle. $$$$
Lean4
theorem finSuccAboveEquiv_apply (p : Fin (n + 1)) (i : Fin n) :
finSuccAboveEquiv p i = ⟨p.succAbove i, p.succAbove_ne i⟩ :=
rfl