Talk:Binary-to-text encoding
Latest comment: 19 years ago by Paolo Liberatore in topic basE91
basE91
Uses 91 characters, and every pair of characters represents either 13 or 14 bits. Since 2^13 < 91*91 < 2^14, two characters can encode all 13-bit strings and some 14-bit strings; since 91*91=8281 and 2^13=8192, there are 89 combinations of two characters that are not used for representing strings of 13 characters. The particular choice is: for a string of 14 bits, if its lowest 13 represent a number greater than or equal to 89, the two characters are used to represent only these 13 bits; otherwise, 14 bits are encoded.
Do not move this explanation to the article; it is undocumented. - Liberatore(T) 13:45, 13 April 2006 (UTC)