import sequtils,strutils
const
    Max_num = 2_000_003
    modnum : int64 = 1_000_000_007

proc powInt(n : int64, m : int64, k = modnum):int64 =
    if m == 0:
        return 1
    elif m == 1:
        return (n mod k)
    if (m mod 2) == 0:
        return powInt((n * n) mod k,m div 2, k) mod k
    else:
        return (powInt((n * n) mod k,m div 2, k) * n) mod k

var
    kaizyou : array[Max_num + 1, int64]
    gyakuKaizyou : array[Max_num + 1, int64]
    
kaizyou[0] = 1
for i in 1..Max_num:
    kaizyou[i] = ((kaizyou[i - 1] * i.int64) mod modnum)
    
gyakuKaizyou[Max_num] = powInt(kaizyou[Max_num], modnum - 2)
for i in countdown(Max_num - 1,0):
    gyakuKaizyou[i] = (gyakuKaizyou[i + 1] * (i + 1)) mod modnum

proc combination(n : int64, k : int64): int64 =
    if n < k:
        return 0
    if n == k:
        return 1
    return (((kaizyou[n] * gyakuKaizyou[n - k]) mod modnum) * gyakuKaizyou[k]) mod modnum

var
    N = stdin.readline.parseInt
    memo : array[560, array[560, int64]]
    m = 1000_000_007
    ans : int64
    
proc F(x,y : int64):int64 =
    if x == 0 and y == 0:
        return 1
    if x < y or y <= 0:
        return 0
    if memo[x][y] > 0:
        return memo[x][y]
    
    memo[x][y] = (F(x - 1, y - 1) mod m + y * F(x - 1, y) mod m) mod m
    return memo[x][y]
        
for y in 1..(N.int64):
    for x in 1..(N.int64):
        var
            A = 1.int64
        A = combination(N, x) * F(x, y)
        A = A mod m
        A *= powInt((y * (y - 1) mod m), N.int64 - x)
        A = A mod m
        ans += A
        ans = ans mod m
echo ans