What is excess notation?

Answer 1

Excess notation represents numbers in order using the number at the transition point of the high-order bit as zero. The zero point is taken as the excess number for the high-order bit. This number is declared to be zero. Positive numbers are above it in order and negative numbers are below it in order. For instance, Excess 16 notation indicates that the value for zero is the bit pattern for 16, that is 10000. The bit patterns are 5 bits long. The 16's column is the first column in that length pattern, and when it first changes to a 1 in the counting sequence, we declare that number to be zero. The patterns and their values are assigned by placing 0 to be 10000, that is the "1" indicates the start of the non negative numbers.

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