diminished radix complement

noun1

1. •
   The number which, added to the given n-digit number in radix r, results in rⁿ-1. In binary (r=2), this is the ones' complement; in decimal (r=10), this is the nines' complement.

   • The diminished radix complement of 01100101_2 is 10011010_2.
   • The diminished radix complement of 138053_10 is 861946_10.