map length (tiers :: [[ NoDup Bool ]])  =  [1,2,2]

length (list :: [ NoDup Bool ])  =  5

allUnique (list :: [ NoDup Bool ])  =  True

ratioRepetitions (list :: [ NoDup Bool ])  =  0 % 1

tiers :: [NoDup Bool]  =
  [ [NoDup []]
  , [ NoDup [False]
    , NoDup [True]
    ]
  , [ NoDup [False,True]
    , NoDup [True,False]
    ]
  ]
