摘要
Let v(n) denote the number of representations of n as the sum of six cubes and twobiquadrates of natural numbers. Then for all sufficiently large n, we have v(n)≥1/(48)~2(log16/15)Γ(4/3)~6Γ(5/4)~2?(Γ(5/2))?(n)n^(3/2),where ?(n) =sum from q=1 to ∞ sum from a=1 (a,q)=1 to q q^(-8)S_3(q,a)~6S_4(q,a)~2c(-an/q) S_k(q,a) =sum from r=1 to q e(ar^k/q).
Let v(n) denote the number of representations of n as the sum of six cubes and twobiquadrates of natural numbers. Then for all sufficiently large n, we have v(n)≥1/(48)<sup>2</sup>(log16/15)Γ(4/3)<sup>6</sup>Γ(5/4)<sup>2</sup>?(Γ(5/2))?(n)n<sup>3/2</sup>,where ?(n) =sum from q=1 to ∞ sum from a=1 (a,q)=1 to q q<sup>-8</sup>S<sub>3</sub>(q,a)<sup>6</sup>S<sub>4</sub>(q,a)<sup>2</sup>c(-an/q) S<sub>k</sub>(q,a) =sum from r=1 to q e(ar<sup>k</sup>/q).
基金
Project supported by the Alexander von Humboldt-Fund and the National Natutal Science Foundation of China.