Given a series as shown below:
1 2
3 4 5 6
7 8 9 10 11 12
13 14 15 16 17 18 19 20
..........................
............................
(so on)
Find the sum of Nth row.

Example 1:
Input: N = 2
Output: 18
Explanation: Sum of 2nd row is 3 + 4 +
5 + 6 = 18.
Example 2:
Input: N = 4
Output: 132
Explanation: Sum of 4th row is 132.

Your Task:
You don't need to read or print anything. Your task is to complete the function Nth_rowSum() which takes N as input parameter and returns sum of Nth row modulo 10^{9} + 7.

Expected Time Complexity: O(1)
Expected Space Complexity: O(1)

Constraints:
1 <= N <= 10^{4}

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