I solved that thing in less than 2 minutes too, and bet my pinkie finger nobody would take more than 15 minutes to figure it out.
There is some background of truth in the article, that most people lose the will to be creative (not the ability) over time. But it's over-generalizations galore.
You solved the problem easily because the article name was "overthinking" and it was saying that "children could do this".
You would be absolutely amazed at what that does to your problem solving ability. You actually stop over-thinking. You don't go to your advanced number-theory knowledge you may or may not have and you look for a simple solution.
Sorry, but everyone that read the article and then solved the problem is tainted.
I could not solve the problem and gave up after an hour. I gave the problem to my preschool child and they also could not figure it out. Since the article didn't provide a method for 'childifying' our minds I guess the only solution is suicide.
There is some background of truth in the article, that most people lose the will to be creative (not the ability) over time. But it's over-generalizations galore.