n = int(input())
MOD = 10**9+7
N = n+4
dp1 = [0]*N
dp2 = [0]*N
dp3 = [0]*N
dp1[1] = dp2[2] = dp3[3] = 1
for i in range(n+1):
    dp1[i] %= MOD
    dp2[i] %= MOD
    dp3[i] %= MOD
    dp2[i+2] += dp1[i]
    dp3[i+3] += dp1[i]
    dp3[i+3] += dp2[i]
    dp1[i+1] += dp2[i]
    dp1[i+1] += dp3[i]
    dp2[i+2] += dp3[i]
print((dp1[n]+dp2[n]+dp3[n])%MOD)