#include <bits/stdc++.h>
#define ll long long
using namespace std;
const int mod=1e9+7;
const int N=351;
ll dp[N][N];
ll fak[N];
ll cr[N][N];
ll bpow(ll x,ll y){
    if(y==0){
        return 1;
    }
    ll g=bpow(x,y/2);
    g*=g;
    g%=mod;
    if(y%2==0){
        return g;
    }
    g*=x;
    g%=mod;
    return g;
}
ll inverse(ll x){
    return bpow(x,mod-2);
}
ll c(ll x,ll y){
    ll e=fak[y]*(fak[x-y]);
    e%=mod;
    e=inverse(e);
    e*=fak[x];
    e%=mod;
    return e;
}
int main(){
    int n;
    cin>>n;
    fak[0]=1;
    for(ll i=1;i<=n;++i){
        fak[i]=fak[i-1]*i;
        fak[i]%=mod;
    }
    for(int i=0;i<=n;++i){
        for(int j=0;j<=i;++j){
            cr[i][j]=c(i,j);
        }
    }
    for(int i=1;i<=n;++i){
        for(int j=1;j<=n;++j){
            for(int k=0;k<=j;++k){
                if(k==i){
                    dp[i][j]+=(bpow(i-1,j-k)*c(j,k));
                    dp[i][j]%=mod;
                    continue;
                }
                dp[i][j]+=(dp[i-1][j-k]*cr[j][k]);
                dp[i][j]%=mod;
            }
        }
    }
    cout<<dp[n][n];
    return 0;
}
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