map length (tiers :: [[ [Nat] ]])  =  [1,1,2,4,8,16,...]

length (list :: [ [Nat] ])  =  Infinity

allUnique (list :: [ [Nat] ])  =  True

ratioRepetitions (list :: [ [Nat] ])  =  0 % 1

tiers :: [[Nat]]  =
  [ [[]]
  , [[0]]
  , [ [0,0]
    , [1]
    ]
  , [ [0,0,0]
    , [0,1]
    , [1,0]
    , [2]
    ]
  , [ [0,0,0,0]
    , [0,0,1]
    , [0,1,0]
    , [0,2]
    , [1,0,0]
    , [1,1]
    , [2,0]
    , [3]
    ]
  , [ [0,0,0,0,0]
    , [0,0,0,1]
    , [0,0,1,0]
    , [0,0,2]
    , [0,1,0,0]
    , [0,1,1]
    , [0,2,0]
    , [0,3]
    , [1,0,0,0]
    , [1,0,1]
    , [1,1,0]
    , [1,2]
    , [2,0,0]
    , [2,1]
    , [3,0]
    , [4]
    ]
  , ...
  ]
