A194942 List of seven normalized ternary Abelian squarefree words.

0, 0, 1, 0, 1, 0, 0, 1, 2, 0, 1, 0, 2, 0, 1, 2, 0, 0, 1, 2, 1, 0, 1, 0, 2, 0, 0, 1, 0, 2, 1, 0, 1, 2, 0, 1, 0, 1, 2, 0, 2, 0, 1, 2, 1, 0, 0, 1, 0, 2, 0, 1, 0, 1, 0, 2, 1, 0, 0, 1, 0, 2, 1, 2, 0, 1, 2, 0, 1, 0, 0, 1, 2, 1, 0, 1, 0, 1, 0, 2, 0, 1, 0, 0, 1, 0, 2, 1, 0, 1, 0, 1, 2, 1, 0, 1, 2

Offset: 1

Author

Franklin T. Adams-Watters, Sep 05 2011

Keywords

• nonn
• fini
• full
• tabf

Comments

Lexicographically ordered list of words of increasing length L=1,2,3,... over the alphabet {0,1,2}, without those which contain two adjacent subsequences with the same multiset of symbols, regardless of internal order. Only those words where the symbols appear in order are included; e.g., {0, 1, 0, 2}, but not {0, 2, 0, 1} or {1, 2, 1, 0}.

The row lengths in number of sequences are 1, 1, 2, 3, 5, 5, 3, for total row lengths of 1, 2, 6, 12, 25, 30, 21.

Examples

			The rows are:
{{0}},
{{0, 1}},
{{0, 1, 0}, {0, 1, 2}},
{{0, 1, 0, 2}, {0, 1, 2, 0}, {0, 1, 2, 1}},
{{0, 1, 0, 2, 0}, {0, 1, 0, 2, 1}, {0, 1, 2, 0, 1}, {0, 1, 2, 0, 2}, {0, 1, 2, 1, 0}},
{{0, 1, 0, 2, 0, 1}, {0, 1, 0, 2, 1, 0}, {0, 1, 0, 2, 1, 2}, {0, 1, 2, 0, 1, 0}, {0, 1, 2, 1, 0, 1}},
{{0, 1, 0, 2, 0, 1, 0}, {0, 1, 0, 2, 1, 0, 1}, {0, 1, 2, 1, 0, 1, 2}}
		

Links

• V. Keränen, New Abelian Square-Free DT0L-Languages over 4 Letters

Crossrefs

Cf. A194923 (includes non-normalized sequences).