#P2568. Count of Prime GCD Pairs
Count of Prime GCD Pairs
Count of Prime GCD Pairs
Given a positive integer \(n\), count the number of pairs \((x, y)\) where \(1 \le x, y \le n\) such that \(\gcd(x, y)\) is a prime number.
inputFormat
The input consists of a single integer \(n\).
outputFormat
Output a single integer representing the number of pairs \((x, y)\) satisfying the condition.
sample
1
0