How many positive integers not exceeding 90 are relatively prime to 90?
Note
This is Euler's totient value φ(90). Removing multiples of its prime factors gives φ(90) = 24.
How many positive integers not exceeding 90 are relatively prime to 90?
This is Euler's totient value φ(90). Removing multiples of its prime factors gives φ(90) = 24.