square_free_word (668B)
1 # Square free word 2 3 A [word] which does not contain a nonempty [factor] which is a [square], i.e., a [word] which is not a [repetitive_string] 4 5 There are infinite square-free words over a ternary alphabet 6 7 We can generate them by backtracking, this gives the [lexicographically] smallest such word, i.e., the [lexicographically_smallest_squarefree_ternary] 8 - if we disallow backtracking, we get an infinite square-free word with the natural numbers as alphabet, which is in fact the [ruler_sequence] 9 10 Up: [square_word], [factor_avoidance] 11 12 See also: [square_free_word_language], [repetitive_string], [thue_morse_sequence], [cube_free_word] 13 14 Aliases: square free words