We exhibit a new class of grammars with the help of weightfunctions. They are characterized by decreasing the weight during the derivation process. A decision algorithm for the emptiness problem is developed. This class contains non-contextfree grammars. The corresponding language class is identical to the class of ultralinear languages.
@article{ITA_2004__38_1_19_0,
author = {Brandt, Ulrike and Delepine, Ghislain and Walter, Hermann K.-G.},
title = {Weightreducing grammars and ultralinear languages},
journal = {RAIRO - Theoretical Informatics and Applications - Informatique Th\'eorique et Applications},
volume = {38},
year = {2004},
pages = {19-25},
doi = {10.1051/ita:2004001},
mrnumber = {2059026},
zbl = {1084.68058},
language = {en},
url = {http://dml.mathdoc.fr/item/ITA_2004__38_1_19_0}
}
Brandt, Ulrike; Delepine, Ghislain; Walter, Hermann K.-G. Weightreducing grammars and ultralinear languages. RAIRO - Theoretical Informatics and Applications - Informatique Théorique et Applications, Tome 38 (2004) pp. 19-25. doi : 10.1051/ita:2004001. http://gdmltest.u-ga.fr/item/ITA_2004__38_1_19_0/
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