Some improvements to the extendability of ternary linear codes

For a ternary [n,k,d] code with d≡1 or 2 (mod 3), k 3, the diversity (Φ0,Φ1) given by is important to know about the extendability of , where Ai stands for the number of codewords with weight i. As a continuation of [T. Maruta, Extendability of ternary linear codes, Des. Codes Cryptogr. 35 (2005) 175–190], we prove all the conjectures posed in this paper, which yield some improvements to the extendability and non-extendability of ternary linear codes. We also give the necessary and sufficient conditions for the extendability of for the case when k=4.