Computing the Length of Sum of Squares and Pythagoras Element in a Global Field

• Autorzy: Darkey-Mensah Mawunyo Kofi , Rothkege Beata

Identyfikatory

DOI

10.3233/FI-2021-2100

• Języki publikacji: EN

Abstrakty

EN

This paper presents algorithms for computing the length of a sum of squares and a Pythagoras element in a global field K of characteristic different from 2. In the first part of the paper, we present algorithms for computing the length in a non-dyadic and dyadic (if K is a number field) completion of K. These two algorithms serve as subsidiary steps for computing lengths in global fields. In the second part of the paper we present a procedure for constructing an element whose length equals the Pythagoras number of a global field, termed a Pythagoras element.

Słowa kluczowe

EN

algorithms; uadratic forms; global fields; length; sum of squares; Pythagoras number; Pythagoras element

• Wydawca: IOS Press
• Czasopismo: Fundamenta Informaticae
• Rocznik: 2021
• Tom: Vol. 184, nr 4
• Strony: 297--306
• Opis fizyczny: Bibliogr. 18 poz.

Twórcy

autor

Darkey-Mensah Mawunyo Kofi

• Institute of Mathematics, University of Silesia, Poland

autor

Rothkege Beata

• Institute of Mathematics, University of Silesia, Poland

Bibliografia

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Uwagi

Opracowanie rekordu ze środków MEiN, umowa nr SONP/SP/546092/2022 w ramach programu "Społeczna odpowiedzialność nauki" - moduł: Popularyzacja nauki i promocja sportu (2022-2023). (PL)