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RngTime Limit: 2000/1000 MS (Java/Others) Memory Limit: 262144/262144 K (Java/Others)Total Submission(s): 1400 Accepted Submission(s): 848 Problem Description Avin is studying how to synthesize data. Given an integer n, he constructs an interval using the following method: he first generates a integer r between 1 and n (both inclusive) uniform-randomly, and then generates another integer l between 1 and r (both inclusive) uniform-randomly. The interval [l, r] is then constructed. Avin has constructed two intervals using the method above. He asks you what the probability that two intervals intersect is. You should print p* ${q^{(-1)}}$(MOD 1, 000, 000, 007), while $\frac{p}{q}$ denoting the probability. Input Just one line contains the number n (1 ≤ n ≤ 1, 000, 000). Output Print the answer. Sample Input
Sample Output
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