N=int(input())
dp=[[0 for j in range(10)] for i in range(N+1)]
dp[0][0]=1
mod=10**9+7

for i in range(N):
    for j in range(10):
        for d in range(1,10):
            if j<=d:
                dp[i+1][d]+=dp[i][j]

ans=1
for i in range(1,N+1):
    ans+=sum(dp[i])
    ans%=mod
print(ans)