Define the function f(x) that equals to the number of divisors of x. Given two integers a and b (a≤b), calculate the sum f(a)+f(a+1)+...+f(b).
Each line contains two integers a and b (1≤a≤b≤231−1). The input is terminated by a line with a=b=0.
For each test case print in a separate line the value of f(a)+f(a+1)+...+f(b).