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arXiv · 0712.0408

Inverse Problems for Representation Functions in Additive Number Theory

Melvyn B. Nathanson
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Abstract

For every positive integer h, the representation function of order h associated to a subset A of the integers or, more generally, of any group or semigroup X, counts the number of ways an element of X can be written as the sum (or product, if X is nonabelian) of h not necessarily distinct elements of X. The direct problem for representation functions in additive number theory begins with a subset A of X and seeks to understand its representation functions. The inverse problem for representation functions starts with a function f:X ->N_0 U {\infty} and asks if there is a set A whose representation function is f, and, if the answer is yes, to classify all such sets. This paper is a survey of recent progress on the inverse representation problem.

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Melvyn B. Nathanson. 2007-12-03. Inverse Problems for Representation Functions in Additive Number Theory. https://arxiv.org/abs/0712.0408

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