Balanced word: Difference between revisions
Tags: Mobile edit Mobile web edit |
Tags: Mobile edit Mobile web edit |
||
| Line 6: | Line 6: | ||
== Properties == | == Properties == | ||
* A balanced word or necklace in ''N'' letters has a [[maximum variety]] bound of <math> N \choose {\lceil N/2 \rceil}</math>. | * A balanced word or necklace in ''N'' letters has a [[maximum variety]] bound of <math> N \choose {\lceil N/2 \rceil}</math>. | ||
* If ''w'' is an aperiodic infinite balanced word, then ''w'' is constructed via a finite sequence of ''congruence substitutions'' from infinite balanced words on 2 letters. A congruence substitution involves replacing the ''k''th letter | * If ''w'' is an aperiodic infinite balanced word, then ''w'' is constructed via a finite sequence of ''congruence substitutions'' from infinite balanced words on 2 letters. A congruence substitution involves replacing the ''k''th occurrence of a fixed letter ''j'' in ''w'' with the ''k''th letter of ''a'' where ''a'' has a set of letters disjoint from that of ''w'' for all positive integers ''k''.<ref>Brauner, N., Crama, Y., Delaporte, E., Jost, V., & Libralesso, L. (2019). Do balanced words have a short period?. Theoretical Computer Science, 793, 169-180.</ref> | ||
== Generalizations == | == Generalizations == | ||