Jacobsthal Numbers Modulo
The Jacobsthal sequence is J(0)=0, J(1)=1, J(n)=J(n−1)+2J(n−2). Print J(N) modulo 109+7.
Input: one integer N.
Output: the value modulo 109+7.
Constraints:
- 1 ≤ N ≤ 1018
Sample Tests
Input 1
4
Output 1
10
Input 2
1
Output 2
2
Input 3
1000000000000000000
Output 3
812984175
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