CF758F.Geometrical Progression

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题目描述

For given nn , ll and rr find the number of distinct geometrical progression, each of which contains nn distinct integers not less than ll and not greater than rr . In other words, for each progression the following must hold: l<=ai<=rl<=a_{i}<=r and aiaja_{i}≠a_{j} , where a1,a2,...,ana_{1},a_{2},...,a_{n} is the geometrical progression, 1<=i,j<=n1<=i,j<=n and iji≠j .

Geometrical progression is a sequence of numbers a1,a2,...,ana_{1},a_{2},...,a_{n} where each term after first is found by multiplying the previous one by a fixed non-zero number dd called the common ratio. Note that in our task dd may be non-integer. For example in progression 4,6,94,6,9 , common ratio is .

Two progressions a1,a2,...,ana_{1},a_{2},...,a_{n} and b1,b2,...,bnb_{1},b_{2},...,b_{n} are considered different, if there is such ii ( 1<=i<=n1<=i<=n ) that aibia_{i}≠b_{i} .

输入格式

The first and the only line cotains three integers nn , ll and rr ( 1<=n<=107,1<=l<=r<=1071<=n<=10^{7},1<=l<=r<=10^{7} ).

输出格式

Print the integer KK — is the answer to the problem.

输入输出样例

  • 输入#1

    1 1 10
    

    输出#1

    10
  • 输入#2

    2 6 9
    

    输出#2

    12
  • 输入#3

    3 1 10
    

    输出#3

    8
  • 输入#4

    3 3 10
    

    输出#4

    2

说明/提示

These are possible progressions for the first test of examples:

  • 11 ;
  • 22 ;
  • 33 ;
  • 44 ;
  • 55 ;
  • 66 ;
  • 77 ;
  • 88 ;
  • 99 ;
  • 1010 .

These are possible progressions for the second test of examples:

  • 6,76,7 ;
  • 6,86,8 ;
  • 6,96,9 ;
  • 7,67,6 ;
  • 7,87,8 ;
  • 7,97,9 ;
  • 8,68,6 ;
  • 8,78,7 ;
  • 8,98,9 ;
  • 9,69,6 ;
  • 9,79,7 ;
  • 9,89,8 .

These are possible progressions for the third test of examples:

  • 1,2,41,2,4 ;
  • 1,3,91,3,9 ;
  • 2,4,82,4,8 ;
  • 4,2,14,2,1 ;
  • 4,6,94,6,9 ;
  • 8,4,28,4,2 ;
  • 9,3,19,3,1 ;
  • 9,6,49,6,4 .

These are possible progressions for the fourth test of examples:

  • 4,6,94,6,9 ;
  • 9,6,49,6,4 .
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