Let r= 2d-1 + 1. We investigate the diophantine inequality|∑i=1rλiΦi(xi,yi)+η||<(max?1≤i≤r{|xi|,|yi|})-σwhere Φi(x, y) ∈Z[x, y] (1≤i≤r) are nondegenerate forms of degree d= 3 or 4.
CookR J. The value of additive forms at prime arguments. J Théor Nombres Bordeaux, 2001, 13: 77-91 doi: 10.5802/jtnb.305
9
DavenportH. Analytic Methods for Diophantine Equations and Diophantine Inequalities. 2nd ed. Cambridge: Cambridge University Press, 2005 doi: 10.1017/CBO9780511542893
10
DavenportH, HeilbronnH. On indefinite quadratic forms in five variables. J Lond Math Soc, 1946, 21: 185-193 doi: 10.1112/jlms/s1-21.3.185
11
HarveyM P. Cubic diophantine inequalities involving a norm form. Int J Number Theory, 2011, 7(8): 2219-2235 doi: 10.1142/S1793042111005052
12
TitchmarshE C. The Theory of the Riemann Zeta-Function. 2nd ed. Oxford: Oxford University Press, 1986
13
WatsonG L. On indefinite quadratic forms in five variables. Proc Lond Math Soc, 1953, 3(3): 170-181 doi: 10.1112/plms/s3-3.1.170
14
WooleyT D. On Weyl’s inequality, Hua’s lemma and exponential sums over binary forms. Duke Math J, 1999, 100: 373-423 doi: 10.1215/S0012-7094-99-10014-7
15
WooleyT D. Vinogradov’s mean value theorem via efficient congruencing. Ann Math, 2012, 175: 1575-1627 doi: 10.4007/annals.2012.175.3.12