import numpy as np
MOD=10**9+7
a=np.array([[0,1],[3,2]],dtype=np.int64)
def pow_mat(a,n):
    ret=np.eye(2,dtype=np.int64)
    while n>0:
        if n%2==1:
            ret=np.dot(ret,a)%MOD
        a=np.dot(a,a)%MOD
        n//=2
    return ret
n=int(input())
a=pow_mat(a,n)
print(a[0][0])