Bit floating sequence
05AB1E, 10 bytes

LRL˜Íoî.¥ï


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L                 # range [1..input]
 R                # reversed
  L               # convert each to a range: [[1..input], [1..input-1], ..., [1]]
   ˜              # flatten
    Í             # subtract 2 from each
     o            # 2**each
      î           # round up (returns a float)
       ï          # convert to integer
        .¥        # undelta