Abstract
The Cauchy functional equation is not only the most important single functional equation, it is also central to regular variation. Classical Karamata regular variation involves a functional equation and inequality due to Goldie; we study this, and its counterpart in Beurling regular variation, together with the related Gołąb–Schinzel equation.
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To Ranko Bojanić on his 90th birthday.
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Bingham, N.H., Ostaszewski, A.J. Cauchy’s functional equation and extensions: Goldie’s equation and inequality, the Gołąb–Schinzel equation and Beurling’s equation. Aequat. Math. 89, 1293–1310 (2015). https://doi.org/10.1007/s00010-015-0350-6
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DOI: https://doi.org/10.1007/s00010-015-0350-6