MOD = 10**9+7
N = int(input())
if N==1:
    print(1)
elif N==2:
    print(1)
else:
    dp = [[0 for _ in range(4)] for _ in range(N+1)]
    for j in range(1,4):
        dp[N][j] = 1
    for i in range(N-1,0,-1):
        if i<=N-2:
            dp[i][1] = dp[i+2][2]
            if i>=3:
                dp[i][3] = dp[i+2][2]
        if i<=N-3:
            dp[i][1] = (dp[i][1]+dp[i+3][3])%MOD
            if i>=2:
                dp[i][2] = dp[i+3][3]
        if i>=2:
            dp[i][2] = (dp[i+1][1]+dp[i][2])%MOD
        if i>=3:
            dp[i][3] = (dp[i+1][1]+dp[i][3])%MOD
    print((dp[1][1]+dp[2][2]+dp[3][3])%MOD)