AoPS Wiki talk:Problem of the Day/July 6, 2011
Problem
AoPSWiki:Problem of the Day/July 6, 2011
Solution
This Problem of the Day needs a solution. If you have a solution for it, please help us out by adding it.
Trivial Case
:
"Solution"
$1+11+\cdots+\underbrace{111\cdots 111}_{n}} = n + 10(n-1) + 100(n-2) + \cdots + 10^{n-1}(n-(n-1)$ (Error compiling LaTeX. Unknown error_msg). This can be expressed as the summation: