Goal:
  
  T : Type
  Listable_T : Listable T
  FinitelyListable_T : FinitelyListable T
  v : T
  ============================
   (forall offset n : nat,
    forallb (fun '(n0, t) => n0 == find_index t)
      (combine (seq offset (length (list_all T))) (list_all T)) ->
    nth_error (list_all T) n = Some v -> find_index v = offset + n)


DEBUG:Going to execute:
induction (list_all T) as [| x xs IHxs]

Goals:
  
  T : Type
  Listable_T : Listable T
  FinitelyListable_T : FinitelyListable T
  v : T
  ============================
   (forall offset n : nat,
    forallb (fun '(n0, t) => n0 == find_index t)
      (combine (seq offset (length [])) []) ->
    nth_error [] n = Some v -> find_index v = offset + n)

  
  T : Type
  Listable_T : Listable T
  FinitelyListable_T : FinitelyListable T
  v : T
  x : T
  xs : list T
  IHxs : forall offset n : nat,
         forallb (fun '(n0, t) => n0 == find_index t)
           (combine (seq offset (length xs)) xs) ->
         nth_error xs n = Some v -> find_index v = offset + n
  ============================
   (forall offset n : nat,
    forallb (fun '(n0, t) => n0 == find_index t)
      (combine (seq offset (length (x :: xs))) (x :: xs)) ->
    nth_error (x :: xs) n = Some v -> find_index v = offset + n)


DEBUG:Going to execute:
intros
DEBUG LTAC Evaluated term: (list_all T)