880. Nested Radicals

(x,y) is called a nested radical pair if x and y are non-zero integers such that xy is not a cube of a rational number, and there exist integers a, b and c such that:

x3+y3=a3+b3+c3

For example, both (4,125) and (5,5324) are nested radical pairs:

43+1253=13+23+4353+53243=23+203+253

Let H(N) be the sum of |x|+|y| for all the nested radical pairs (x,y) where |x||y|N. For example, H(103)=2535.

Find H(1015). Give your answer modulo 10313+2.

880. 嵌套根式

若非零整数 x,y 满足:xy 不是某有理数的立方,且存在正整数 abc 使得:

x3+y3=a3+b3+c3

则称 (x,y) 是一个 嵌套根式对。例如,因为如下等式成立,所以 (4,125)(5,5324) 都是嵌套根式对。

43+1253=13+23+4353+53243=23+203+253

H(N) 为所有满足 |x||y|N 的嵌套根式对 (x,y)|x|+|y| 之和。已知 H(103)=2535

H(1015)(10313+2) 之值。


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