1. A digital error detecting apparatus comprising means for storing a data word containing up to N-1 bits in error where N is the number of bits in said data word; and means responsive to said means for storing said data word for generating a unique syndrome word for each one of a plurality of possible error patterns in said data word, wherein said unique syndrome word generating means comprises: means for generating a first syndrome word corresponding to the location of bits in error in said data word; means for changing the relative significance of the bits in said data word after said generating of said first syndrome word; means for generating a succeeding syndrome word corresponding to the bits in error in said data word after each such change in significance; and means for combining said first and second succeeding syndrome words in a predetermined manner.