Waring's problem for pseudo-polynomials
Manfred G. Madritsch
TL;DR
This work extends Waring’s problem to sums of floor values of a pseudo-polynomial, proving an asymptotic count for representations $r_{f,s}(N)$ with leading term governed by a Gamma-weighted power of $N$ when $s$ exceeds a explicit threshold. The authors adapt the circle method, decompose the unit interval into major and minor arcs, and compute the main term via a singular integral that yields Gamma-function constants, while bounding the minor-arc contribution through refined exponential-sum estimates anchored in Vinogradov's mean value theorem. Key innovations include handling non-integer exponents in the pseudo-polynomial, controlling the floor-function with Fourier-analytic tools, and extending prior results that required $c>12$ to the broader range $c>1$. The results significantly advance Waring-type representations for non-classical summands and provide a rigorous asymptotic formula with an explicit error exponent. The methods integrate classical circle-method techniques with modern mean-value bounds to accommodate the fractional exponents appearing in $f$.
Abstract
Waring's problem has a long history in additive number theory. In its original form it deals with the representability of every positive integer as sum of $k$-th powers with integer $k$. Instead of these powers we deal with pseudo-polynomials in this paper. A pseudo-polynomial is a ``polynomial'' with at least one exponent not being an integer. Our work extends earlier results on the related problem of Waring for arbitrary real powers $k>12$ by Deshouillers and Arkhipov and Zhitkov.
