Claims

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2009_06_18_ford_luca_pomerance: Ford, Luca and Pomerance prove that Euler's totient and the sum of divisors take infinitely many common values, with at least exp((log log x)^alpha) of them up to x; refereed in the Bulletin of the London Mathematical Society.

2011_01_01_garaev: Garaev proves that for every A there are at least exp((log log x)^A) common values of Euler's totient and the sum of divisors up to x, which answers the question; refereed in the Moscow Journal of Combinatorics and Number Theory.

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