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On three-variable expanders over finite valuation rings

  • Le Quang Ham , Nguyen Van The , Phuc D. Tran and Le Anh Vinh EMAIL logo
From the journal Forum Mathematicum

Abstract

Let be a finite valuation ring of order qr. In this paper, we prove that for any quadratic polynomial f(x,y,z)[x,y,z] that is of the form axy+R(x)+S(y)+T(z) for some one-variable polynomials R,S,T, we have

|f(A,B,C)|min{qr,|A||B||C|q2r-1}

for any A,B,C. We also study the sum-product type problems over finite valuation ring . More precisely, we show that for any A with |A|qr-13 then max{|AA|,|Ad+Ad|}, max{|A+A|,|A2+A2|}, max{|A-A|,|AA+AA|}|A|23qr3, and |f(A)+A||A|23qr3 for any one variable quadratic polynomial f.

MSC 2010: 05D99

Communicated by Christopher D. Sogge


Funding statement: The research is funded by the National Foundation for Science and Technology Development Project 101.99-2019.318.

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Received: 2020-08-02
Revised: 2020-08-17
Published Online: 2020-10-07
Published in Print: 2021-01-01

© 2020 Walter de Gruyter GmbH, Berlin/Boston

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