mod = 1000000007
n = io.read("*n")
t = {{}, {}, {}}
t[1][1], t[1][2], t[1][3] = 1, 0, 1
t[2][1], t[2][2], t[2][3] = 0, 1, 1
t[3][1], t[3][2], t[3][3] = 0, 0, 1
for i = 4, n do
    t[1][i] = (t[3][i - 1] + t[2][i - 1]) % mod
    t[2][i] = (t[3][i - 2] + t[1][i - 2]) % mod
    t[3][i] = (t[2][i - 3] + t[1][i - 3]) % mod
end
ret = (t[1][n] + t[2][n]) % mod
ret = (ret + t[3][n]) % mod
print(ret)