English
For a Besicovitch SatelliteConfig a and i, the distance dist(a.c(i), a.c(last N)) is bounded by a.r(i) + a.r(last N).
Русский
Для конфигурации спутников Бесиковича расстояние между центрами удерживаемых спутников ограничено суммой соответствующих радиусов.
LaTeX
$$∀ i, dist (a.c i) (a.c (last N)) ≤ a.r i + a.r (last N)$$
Lean4
theorem inter' (i : Fin N.succ) : dist (a.c i) (a.c (last N)) ≤ a.r i + a.r (last N) :=
by
rcases lt_or_ge i (last N) with (H | H)
· exact a.inter i H
· have I : i = last N := top_le_iff.1 H
have := (a.rpos (last N)).le
simp only [I, add_nonneg this this, dist_self]