n = int(input())
MOD = 10**9 + 7

if n == 1:
    print(1) #ケン
    exit()
elif n == 2:
    print(2) #ケンケン、ケンパ
    exit()

# dp[i][j] := 長さiで終わるときの通り数
# jはケンかパーかをbit集合で管理
dp = [[0]*4 for i in range(n+1)]
# 初期化
dp[3][0] = 0
dp[3][1] = 1
dp[3][2] = 1
dp[3][3] = 0

for i in range(3, n):
    dp[i+1][2] = dp[i][0]
    dp[i+1][3] = dp[i][1]
    dp[i+1][1] = dp[i][2] + dp[i][3]
    dp[i+1][0] = dp[i][1]
    dp[i+1][1] %= MOD

ans = 0
for j in range(4):
    ans += dp[n][j]
print(ans % MOD)