> There are several ways to write binary or skew binary numbers: a list of digits; a list of ranks of non-zero digits; a list of weights of non-zero digits. You will be using a list of ranks, smallest first. Each rank is a decimal integer, and is separated from the next rank by a ‘,’. The digit 2 is represented by the rank of the digit appearing twice in the list. Note that this means that only the first two ranks in the list may be equal. A list is started by a ‘[’ and ended by a ‘]’. For example, the decimal number 5 is: [0,0,1]. Decimal 0 is an empty list: [ ].