Varieties of Formal Languages¶
Pin, J. (1986). Varieties of Formal Languages. Plenum Press.
Cited by¶
1 citation across 1 artifact.
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Primes¶
- Monoid
- The classification results are sharp: a language is regular exactly when its syntactic monoid is finite, and star-free exactly when that monoid is aperiodic.
This sourceDevelops the free monoid, the syntactic monoid as a quotient by the syntactic congruence, regularity as finiteness of that monoid, and Schutzenberger's characterisation of star-free languages by aperiodicity.
- The classification results are sharp: a language is regular exactly when its syntactic monoid is finite, and star-free exactly when that monoid is aperiodic.
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