scholarly journals Sign changes of Kloosterman sums and exceptional characters

2018 ◽  
Vol 147 (1) ◽  
pp. 61-75 ◽  
Author(s):  
Sary Drappeau ◽  
James Maynard
Author(s):  
Ping Xi

Abstract We give a corrigendum to the previous paper [ 8] and recover the same quantitative statement: the Kloosterman sum changes sign infinitely often as the modulus runs over squarefree numbers with at most seven prime factors.


Author(s):  
Thomas Morrill ◽  
Dave Platt ◽  
Tim Trudgian

2018 ◽  
Vol 6 (1) ◽  
pp. 259-287 ◽  
Author(s):  
Jonathan Ansari ◽  
Ludger Rüschendorf

AbstractConditionally comonotonic risk vectors have been proved in [4] to yield worst case dependence structures maximizing the risk of the portfolio sum in partially specified risk factor models. In this paper we investigate the question how risk bounds depend on the specification of the pairwise copulas of the risk components Xiwith the systemic risk factor. As basic toolwe introduce a new ordering based on sign changes of the derivatives of copulas. This together with discretization by n-grids and the theory of supermodular transfers allows us to derive concrete ordering criteria for the maximal risks.


Author(s):  
R. W. Bruggeman ◽  
R. J. Miatello ◽  
I. Pacharoni

2004 ◽  
Vol 25 (01) ◽  
pp. 97-102 ◽  
Author(s):  
HONGYAN LIU ◽  
WENPENG ZHANG

2003 ◽  
Vol 55 (2) ◽  
pp. 225-246 ◽  
Author(s):  
William D. Banks ◽  
Asma Harcharras ◽  
Igor E. Shparlinski

AbstractWe extend to the setting of polynomials over a finite field certain estimates for short Kloosterman sums originally due to Karatsuba. Our estimates are then used to establish some uniformity of distribution results in the ring [x]/M(x) for collections of polynomials either of the form f−1g−1 or of the form f−1g−1 + afg, where f and g are polynomials coprime to M and of very small degree relative to M, and a is an arbitrary polynomial. We also give estimates for short Kloosterman sums where the summation runs over products of two irreducible polynomials of small degree. It is likely that this result can be used to give an improvement of the Brun-Titchmarsh theorem for polynomials over finite fields.


1988 ◽  
Vol 56 (1) ◽  
pp. 185-197 ◽  
Author(s):  
J. Kaczorowski ◽  
W. Staś

Sign in / Sign up

Export Citation Format

Share Document