M mamun11 New Member Joined Sep 10, 2014 Messages 9 Gender Male HSC N/A Sep 18, 2014 #1 How many pairs of integers (A,B) are there in the range [1,…,N], such that gcd(A,B)=B? Here, N<=10^9. I want to know the best efficient method to find out the number of pairs with proof .
How many pairs of integers (A,B) are there in the range [1,…,N], such that gcd(A,B)=B? Here, N<=10^9. I want to know the best efficient method to find out the number of pairs with proof .