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On the sum of the square of a prime and a square-free number

Published online by Cambridge University Press:  01 January 2016

Adrian W. Dudek
Affiliation:
Mathematical Sciences Institute, The Australian National University, Acton ACT 2601, Australia email [email protected]
David J. Platt
Affiliation:
Heilbronn Institute for Mathematical Research, University of Bristol, Bristol BS8 1SN, United Kingdom email [email protected]

Abstract

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We prove that every integer $n\geqslant 10$ such that $n\not \equiv 1\text{ mod }4$ can be written as the sum of the square of a prime and a square-free number. This makes explicit a theorem of Erdős that every sufficiently large integer of this type may be written in such a way. Our proof requires us to construct new explicit results for primes in arithmetic progressions. As such, we use the second author’s numerical computation regarding the generalised Riemann hypothesis to extend the explicit bounds of Ramaré–Rumely.

Type
Research Article
Copyright
© The Author(s) 2016 

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