Solutions to p^2 Divides 10^p - 10/Mistake
Jump to navigation
Jump to search
Source Work
1997: David Wells: Curious and Interesting Numbers (2nd ed.):
- The Dictionary
- $487$
Mistake
- One of the only $3$ primes, less than $2^{32}$ such that $p^2$ divides $10 p - 10$. The others are $3$ and $56,598,313$.
Correction
That should read:
- ... such that $p^2$ divides $10^p - 10$.
Otherwise it is just not true:
| \(\ds 3\) | \(\nmid\) | \(\ds 10 \times 3 - 10 = 20\) | ||||||||||||
| \(\ds 487\) | \(\nmid\) | \(\ds 10 \times 487 - 10 = 4860\) |
etc.
Sources
- 1997: David Wells: Curious and Interesting Numbers (2nd ed.) ... (previous) ... (next): $487$