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I am looking for algorithms that compute the inverse of Euler's totient function.

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up vote 4 down vote accepted

Here is a nice article off of wolfram that gives an efficient algorithm for computing the inverse of the Euler totient function.

-Download the invphi.nb file at the bottom

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Thanks but unfortunately I failed to install MathReader on my Linux box. Any references mentioned in the notebook? I'm aware of H. Gupta's 1981 seminal paper but it's not so much of an algorithmic formulation. – user2468 Oct 13 '10 at 6:24
@Mike Singh: No references (but a fairly detailed description of how the program works). – Hans Lundmark Oct 13 '10 at 11:03
Oh thanks. I will try to read it on Mathematica on a lab computer or so. – user2468 Oct 14 '10 at 4:32

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