Problem Description

Having obtained the coveted "Matatabi," you have started playing "Snuke's Growth" in earnest.

Despite being in the city, nature is still a world of survival of the fittest, and the recently picked-up Snuke is completely exhausted. You are trying to restore Snuke's health by feeding him in-game items.

Snuke has a peculiar liking for cards with integers written on them. Watching Snuke happily munching on the cards is a delightful sight. However, you noticed that Snuke does not always rejoice upon eating a card. You discovered the following properties:

• Snuke will be happy when he eats a card with an integer that is coprime with all the integers on the cards he has eaten so far that day. Otherwise, he will be sad.

Today, the card shop has cards with integers ranging from $ A $ to $ B $ inclusive. You decided to buy any number of these cards (from 0 up) and feed all of them to Snuke. You must ensure that Snuke never feels sad.

How many ways are there to buy the cards?

Input Format

The input is given from the standard input in the following format:

$ A $ $ B $

Output Format

Output the number of ways to buy the cards.

Sample Input and Output

Sample Input #1

2 4

Sample Output #1

6

Sample Input #2

5 9

Sample Output #2

20

Sample Input #3

123456789987654321 123456789987654356

Sample Output #3

105728

Notes/Hints

Constraints

• $1 \leq A \leq B \leq 10^{18}$
• $B - A \leq 35$

Sample Explanation 1

All combinations that do not include both the card with $ 2 $ and the card with $ 4 $ satisfy the condition. There are 6 such combinations.

见题面 Input 部分

见题面 Output 部分