Mod = int(1e9) + 7
N = int(input())
C = [[0] * (N + 1) for r in range(N + 1)]
dp = [[0] * (N + 1) for r in range(N + 1)]
dp[0][0] = 1
ans = 0

for r in range(N + 1):
    C[r][0] = C[r][r] = 1
    for c in range(1, r):
        C[r][c] = (C[r - 1][c] + C[r - 1][c - 1]) % Mod
for pair in range(1, N + 1):
    for num in range(1, pair + 1):
        dp[pair][num] = (dp[pair - 1][num - 1] + dp[pair - 1][num] * num) % Mod
        ans = (ans + dp[pair][num] * C[N][pair] *
               pow(num * (num - 1), N - pair, Mod)) % Mod

print(ans)