Timeline for Counting divisors of primes plus or minus 2
Current License: CC BY-SA 4.0
3 events
| when toggle format | what | by | license | comment | |
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| Aug 26, 2018 at 0:24 | comment | added | Gerhard Paseman | Similarly, use multiplicativity of tau to classify numbers whose tau value is a multiple of four versus those that aren't (at most one prime has to have a power that is odd, and is not 3 mod 4.). I think finding how tau distributes mod 4 may enlighten. Gerhard "It's Elementary, My Dear Joseph" Paseman, 2018.08.25. | |
| Aug 26, 2018 at 0:18 | comment | added | Gerhard Paseman | The only numbers with an odd number of divisors are perfect squares. That you see them at all relates to a problem of Landau: are there infinitely many primes which are one more than a square. In your case, two away from a square. Gerhard "Not Often Off By One" Paseman, 2018.08.25. | |
| Aug 26, 2018 at 0:07 | history | asked | Joseph O'Rourke | CC BY-SA 4.0 |