Gray codes for necklaces and Lyndon words of arbitrary base
نویسندگان
چکیده
Recently, a Gray code for unrestricted binary necklaces and their relatives was discovered by Vajnovszki [Discrete Mathematics & Theoretical Computer Science, to appear]. The Gray code is constructed by modifying the classical FKM algorithm for generating necklaces in lexicographic order. We present a generalisation of Vajnovszki’s algorithm, giving a Gray code for necklaces and their relatives over an arbitrarily-large alphabet. Each string in the resulting code differs from adjacent strings in at most three positions. To our knowledge this is the first Gray code for necklaces of arbitrary base. Mathematics Subject Classifications (2000). 68R15, 05A99, 05C45
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