Abstract
LetK be a field of characteristicp>0 andF/K be an algebraic function field. We obtain several results on Galois extensionsE/F with an elementary Abelian Galois group of orderp n.
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(a)
E can be generated overF by some elementy whose minimal polynomial has the specific formT pn−T−z.
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(b)
A formula for the genus ofE is given.
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(c)
IfK is finite, then the genus ofE grows much faster than the number of rational points (as [E∶F] → ∞).
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(d)
We present a new example of a function fieldE/K whose gap numbers are nonclassical.
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This paper was written while the first author was visiting Essen within the exchange program GMD-CNPq. The visit was partially supported by the Alexander von Humboldt-Stiftung.
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Garcia, A., Stichtenoth, H. Elementary Abelianp-extensions of algebraic function fields. Manuscripta Math 72, 67–79 (1991). https://doi.org/10.1007/BF02568266
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DOI: https://doi.org/10.1007/BF02568266