Skip to main content
2 of 4
edited tags
GH from MO
  • 105.2k
  • 8
  • 292
  • 398

Is the set AA+A always bigger than A+A?

Let $A$ be a finite set of real numbers. Is it always the case that $|AA+A| \geq |A+A|$?

My first instinct is that this is obviously true, and there is a one-line proof which I am foolishly overlooking. Can anyone provide one? Of course, any proof would be welcome! Any partial results would also be of interest.