#arc071d. [arc071_d]Infinite Sequence

[arc071_d]Infinite Sequence

Problem Statement

How many infinite sequences a1,a2,...a_1, a_2, ... consisting of {1,...,n{1, ... ,n}} satisfy the following conditions?

  • The nn-th and subsequent elements are all equal. That is, if nleqi,jn \\leq i,j, ai=aja_i = a_j.
  • For every integer ii, the aia_i elements immediately following the ii-th element are all equal. That is, if i<j<kleqi+aii < j < k\\leq i+a_i, aj=aka_j = a_k.

Find the count modulo 109+710^9+7.

Constraints

  • 1leqnleq1061 \\leq n \\leq 10^6

Input

Input is given from Standard Input in the following format:

nn

Output

Print how many sequences satisfy the conditions, modulo 109+710^9+7.


Sample Input 1

2

Sample Output 1

4

The four sequences that satisfy the conditions are:

  • 1,1,1,...1, 1, 1, ...
  • 1,2,2,...1, 2, 2, ...
  • 2,1,1,...2, 1, 1, ...
  • 2,2,2,...2, 2, 2, ...

Sample Input 2

654321

Sample Output 2

968545283