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arXiv · 1506.01902

Additive representation in short intervals, II: sums of two like powers

Joerg Bruedern·Trevor D. Wooley
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Abstract

We establish that, for almost all natural numbers $N$, there is a sum of two positive integral cubes lying in the interval $[N-N^{7/18+\epsilon},N]$. Here, the exponent $7/18$ lies half way between the trivial exponent $4/9$ stemming from the greedy algorithm, and the exponent $1/3$ constrained by the number of integers not exceeding $X$ that can be represented as the sum of two positive integral cubes. We also provide analogous conclusions for sums of two positive integral $k$-th powers when $k\ge 4$.

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Joerg Bruedern, Trevor D. Wooley. 2015-06-05. Additive representation in short intervals, II: sums of two like powers. https://doi.org/10.1007/s00605-016-0936-7

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