Properties of pure codes

In this paper we give some properties of pure codes and several characterizations on two-element pure codes. It is shown that a language is a solid code if and only if it is a comma-free code which is also a d-code. We also show that d-codes, intercodes and solid codes are pure codes.

Keywords:

• Comma-free code
• d-Code
• Intercode
• Pure code

Acknowledgements

The authors would like to thank the referees for their careful reading of the manuscript and useful suggestions. This work was supported by the National Science Council R.O.C. under grant NSC 95-2115-M-040-001.