SOLVED - $250
The density of integers which have two divisors $d_1,d_2$ such that $d_1<d_2<2d_1$ exists and is equal to $1$.
In
[Er79] asks the stronger version with $2$ replaced by any constant $c>1$.
The answer is yes (also to this stronger version), proved by Maier and Tenenbaum [MaTe84]. (Tenenbaum has told me that they received \$650 for their solution.)
See also [449] and [884].
