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arXiv · 1010.5442

The number of solutions of lambda(x)=n

Kevin Ford·Florian Luca
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Abstract

We study the question of whether for each n there is another integer m with lambda(m)=lambda(n), where lambda is Carmichael's function. We give a "near" proof of the fact that this is the case unconditionally, and a complete conditional proof under the Extended Riemann Hypothesis. The main tool is a count of prime chains from paper arXiv:0906.3380.

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Kevin Ford, Florian Luca. 2010-10-26. The number of solutions of lambda(x)=n. https://arxiv.org/abs/1010.5442

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