#pragma GCC optimize("Ofast,unroll-loops")
#include<bits/stdc++.h>
#define ll int
#define ld long double
#define mp make_pair
#define ff first
#define ss second
#define ln "\n"
using namespace std;
const ll INF = 2e9;
const ll MOD = 1e9+7;
void solve(){
ll n, s, f; cin >> n >> s >> f;
if (s>f) swap(s, f);
vector<vector<ll>> dp(n+1, vector<ll>(n+1));
dp[0][0]=1;
for (ll i=1; i<=n; i++){
for (ll j=0; j<=n; j++){
if (i<s){
if (j+1<=n) dp[i][j]=dp[i-1][j+1]*(j+1)%MOD*j%MOD;
if (j-1>=0) dp[i][j]=(dp[i][j]+dp[i-1][j-1])%MOD;
}else if (i==s){
dp[i][j]=dp[i-1][j]*(j)%MOD;
// if (j-1>=0) dp[i][j]=(dp[i][j]+dp[i-1][j-1])%MOD;
}else if (i>s and i<f){
if (j+1<=n) dp[i][j]=dp[i-1][j+1]*j%MOD*j%MOD;
if (j-1>=0) dp[i][j]=(dp[i][j]+dp[i-1][j-1])%MOD;
}else if (i==f){
if (n%2==0){
dp[i][j] = dp[i-1][j];
}else{
if (j+1<=n) dp[i][j] = dp[i-1][j+1]*(j)%MOD;
}
}else{
if (j+1<=n) dp[i][j]=dp[i-1][j+1]*(j+1)%MOD*j%MOD;
if (j-1>=0) dp[i][j]=(dp[i][j]+dp[i-1][j-1])%MOD;
}
}
}
// for (ll i=0; i<=n; i++){
// for (ll j=0; j<=n; j++){
// cout << dp[i][j] << ' ';
// }
// cout << ln;
// }
ll res=dp[n-1][1];
dp.assign(n+1, vector<ll>(n+1, 0));
dp[0][0]=1;
for (ll i=1; i<=n; i++){
for (ll j=0; j<=n; j++){
if (i<s){
if (j+1<=n) dp[i][j]=dp[i-1][j+1]*(j+1)%MOD*j%MOD;
if (j-1>=0) dp[i][j]=(dp[i][j]+dp[i-1][j-1])%MOD;
}else if (i==s){
// dp[i][j]=dp[i-1][j]*(j)%MOD;
if (j-1>=0) dp[i][j]=(dp[i][j]+dp[i-1][j-1])%MOD;
}else if (i>s and i<f){
if (j+1<=n) dp[i][j]=dp[i-1][j+1]*j%MOD*j%MOD;
if (j-1>=0) dp[i][j]=(dp[i][j]+dp[i-1][j-1])%MOD;
}else if (i==f){
if (n%2){
dp[i][j] = dp[i-1][j];
}else{
if (j+1<=n) dp[i][j] = dp[i-1][j+1]*(j)%MOD;
}
}else{
if (j+1<=n) dp[i][j]=dp[i-1][j+1]*(j+1)%MOD*j%MOD;
if (j-1>=0) dp[i][j]=(dp[i][j]+dp[i-1][j-1])%MOD;
}
}
}
// for (ll i=0; i<=n; i++){
// for (ll j=0; j<=n; j++){
// cout << dp[i][j] << ' ';
// }
// cout << ln;
// }
/*
* dp[i][x] => dp[i-1][x+1]*(x+1)*x+dp[i-1][x-1];
*
*/
cout << (res+dp[n-1][1])%MOD << ln;
}
int main(){
ios_base::sync_with_stdio(false);
cin.tie(nullptr);
ll t=1;
// cin >> t;
while (t--) {
solve();
}
}
