∀ {α : Type u_1} [inst : BEq α] [inst_1 : LawfulBEq α] {xs : List α} {xc : (x : α) × Fin (List.count x xs)},
  ↑(cast ⋯ xc.snd) + 1 ≤ (List.filter (fun x => x == (xs.idxToSigmaCount (xs.sigmaCountToIdx xc)).fst) xs).length →
    ↑(cast ⋯ xc.snd) < (List.findIdxs (fun x => x == (xs.idxToSigmaCount (xs.sigmaCountToIdx xc)).fst) xs).length