Refinements of Lagrange's four-square theorem

2017/03/09 by Goldmakher, Leo, Pollack, Paul
#11E25 #FOS: Mathematics #Number Theory (math.NT)

paper · doi:10.48550/arxiv.1703.03092

Abstract

A well-known theorem of Lagrange asserts that every nonnegative integer n can be written in the form a²+b²+c²+d², where a,b,c,d ∈ ℤ. We characterize the values assumed by a+b+c+d as we range over all such representations of n.

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