Hello, I came across this problem and I wasn't entirely sure on how to do it. Seeing if someone can give me a hand with it? Any help is greatly appreciated, thanks!
Yes thats right.
An easy way to see this is all perfect squares are of the form , all perfect cubes are of the form and all numbers that are both a perfect square and a perfect cube are . Using inclusion exculsion, that means for any the number of numbers that are a perfect square or a perfect cube less than N are