Exact lower bounds on the codelength of three-step permutation-decodable cyclic codes

The exact lower bounds on codelength n for three-step (T, U) permutation decodable binary cyclic codes of even-valued error number t (t>or=4) are presented. Since the derivation of these results involves only the error position, the results are applicable to cyclic codes over GF(2/sup m/).<
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