#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define FORI(i, n) for(ll i = 0; i < n; i++)
#define FOR(i, n) for(ll i = 1; i <= n; i++)
typedef vector<ll> vl;
typedef set<ll> setl;
#define ff first
#define ss second
#define all(v) v.begin(), v.end()
#define pll pair<ll, ll>
#define db double
#define nll cout << "\n"
#define nl "\n"
#define sync ios_base::sync_with_stdio(0), cin.tie(0), cout.tie(0);
const ll mod = 1e9 + 7;
const int MAX = 2000 + 5;
ll n, m, k, res;
ll dp[MAX][MAX];
void solve(){
cin >> n >> m >> k;
dp[1][1] = 1;
for(ll i = 2; i <= n; i++){
FOR(j, i){
if(i == m|| i == k){
dp[i][j] = (dp[i - 1][j - 1] + dp[i - 1][j]) % mod;
}
else{
dp[i][j] = ((dp[i - 1][j - 1] * (j - (i > m) - (i > k)) ) % mod + (dp[i - 1][j + 1] * j) % mod) % mod;
}
}
}
cout << dp[n][1] % mod;
}
signed main(){
// freopen("input.txt","r",stdin);
// freopen("output.txt","w",stdout);
sync;
ll t = 1;
// cin >> t;
FOR(i, t){
// cout << "Case #" << i << ": ";
solve();
}
}
