A linear code

over GF

is good for

-error-correction and error detection if

for all

, where

is the probability of an undetected error after a codeword in

is transmitted over a

-ary symmetric channel with error probability

and correction is performed for all error patterns with

or fewer errors. A sufficient condition for a code to be good is derived. This sufficient condition is easy to check, and examples to illustrate the method are given.