13.1.4.6 Digits in a Radix

What qualifies as a digit depends on the radix (an integer between 2 and 36, inclusive). The potential digits are:

0 1 2 3 4 5 6 7 8 9 A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

Their respective weights are 0, 1, 2, ... 35. In any given radix n, only the first n potential digits are considered to be digits. For example, the digits in radix 2 are 0 and 1, the digits in radix 10 are 0 through 9, and the digits in radix 16 are 0 through F.

Case is not significant in digits; for example, in radix 16, both F and f are digits with weight 15.