P = int(input())

N = str(10**P-1)

dp = [[[0]*3 for _ in range(2)] for _ in range(len(N)+1)]
dp[0][0][0] = 1
for i in range(len(N)):
    for j in range(2):
        for k in range(3):
            for l in range(10):
                dp[i+1][j or l==3][(k*10+l)%3] += dp[i][j][k]

ans = sum(dp[len(N)][1])+dp[len(N)][0][0]-1
ans += 10**P%3 == 0

print(ans)