supported by the National Natural Science Foundation of China(No.11201107);the China Scholarship Council
Let Pr denote an almost prime with at most r prime factors, counted according to multiplicity. In the present paper, it is proved that for any sufficiently large even integer n, the equation n=x^3+p1^3+p2^3+p3^3+p...
Supported by National Natural Science Foundation of China(11201107)
Let f(x) be an irreducible polynomial of degree m ≥ 2 with integer coefficients,and let r(n) denote the number of solutions x of the congruence f(x) ≡ 0(mod n) satisfying0 ≤ x < n. Define ?(x) =Σ 1≤n≤x r(n)-αx,...
Supported by NSFC(No.11201107,No.11271283,No.11501435);the Natural Science Basic Research Plan in Shaanxi Province of China(No.2016JM1013);the Starting Research Fund for Doctors of Xi'an Polytechnic University(No.BS1508)
Supported by the National Natural Science Foundation of China(11201107,11271283,11501435);Supported by the Natural Science Foundation of Anhui Province(1208085QA01)
It is proved that if λ1,λ2,…,λ7 are nonzero real numbers, not all of the same sign and not all in rational ratios, then for any given real numbers η and σ, 0 〈 σ 〈 1/16, the inequality |λ1x1^2+λ2x2^2+∑i...