Goal:
  
  A : Type
  n : nat
  a : A
  IHn : List.rev (repeat a n) = repeat a n
  cstr : BinInt.Z.le BinNums.Z0 (BinInt.Z.of_nat n)
  ============================
   (BinInt.Z.add (BinInt.Z.of_nat n) (BinNums.Zpos BinNums.xH) =
    BinInt.Z.add (BinInt.Z.of_nat n) (BinNums.Zpos BinNums.xH))


DEBUG:Going to execute:
idtac