Abstract
It is always an interesting subject to investigate whether a three-element language is a code or not. In this paper, we consider a special class of three-element languages, where two words have the same length which is less than the length of the third word. We give a necessary and sufficient condition to state whether a three-element language in this class is a code. This result partially resolves the problem proposed by Professor H. J. Shyr in 1990s.
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The authors would like to thank the referees for their careful reading of the manuscript and useful suggestions.
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This work is supported by Applied Basic Research Program of Science and Technology Department of Yunnan Province of China # 2014FB101, Educational Committee Major Natural Science Foundation of Yunnan Province of China # ZD2015013, and National Natural Science Foundation of China # 11261066.
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Chunhua, C., Qing, L. & Di, Y. A first step in characterizing three-element codes. Acta Informatica 55, 445–457 (2018). https://doi.org/10.1007/s00236-017-0309-2
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DOI: https://doi.org/10.1007/s00236-017-0309-2