Regular Tree Languages Definable in FO and in FOmod
We consider regular languages of labeled trees. We give an effective characterization of the regular languages over such trees that are definable in first-order logic in the language of labeled graphs. These languages are the analog on trees of the locally threshold testable languages on strings. We...
| Main Authors: | , |
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| 格式: | Journal article |
| 语言: | English |
| 出版: |
2009
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