Задачи
An Idea of Mr. A
An Idea of Mr. A
Mr. A proposes to his son the following problem:
"Consider two integers n_1 and n_2 such that 1 ≤ n_1 < n_2 ≤ 10^4.
Using the function p:N^{*}→N^{*}, p(n)=2^n, n N^{*} (where N^{*} is the set of positive integers) we define the set
We also define a set of pairs as follows:
Consider the formula:
where gcd(m_1,m_2) is the greatest common divisor of m_1 and m_2. The problem asks to find the number R(n_1,n_2)."
Solve the problem proposed by Mr. A.
Входные данные
The input file consists of a single line having the values for n_1 and n_2, separated by exactly one space.
Выходные данные
For each test, the result will be written to standard output and consists of the value of R(n_1,n_2).
Пример
Входные данные #1
1 34
Выходные данные #1
561