#include <bits/stdc++.h>
using namespace std;
typedef unsigned int uint;
typedef unsigned long long ull;
typedef long long ll;
typedef long double ld;
typedef pair <int, int> pii;
typedef pair <ll, int> pli;
typedef pair <int, ll> pil;
typedef pair <ll, ll> pll;
typedef pair <ld, ld> pdd;
#define cio ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0)
#define cases int _; cin >> _; while(_--)
#define pb push_back
#define eb emplace_back
#define space << " " <<
#define lb lower_bound
#define ub upper_bound
#define F first
#define S second
#define all(v) v.begin(), v.end()
#define rall(v) v.rbegin(), v.rend()
#define Unique(v) v.erase(unique(all(v)), v.end())
#define mset(x) memset(x, 0, sizeof(x))
#define sflush fflush(stdout)
#define cflush cout.flush()
#define yes cout << "YES\n"
#define no cout << "NO\n"
#define nl cout << "\n";
#define binary(len, num) bitset <len> (num)
#define vt vector
#define ar array
#define Mat vt <vt <int> >
template <typename T> istream& operator >> (istream& in, vector<T>& a) {for(auto &x : a) in >> x; return in;};
template <typename T> ostream& operator << (ostream& out, vector<T>& a) {for(auto &x : a) out << x << ' '; return out;};
int read(){
int w = 1, c, ret;
while((c = getchar()) > '9' || c < '0'){
w = (c == '-' ? -1 : 1);
}
ret = c - '0';
while((c = getchar()) >= '0' && c <= '9'){
ret = ret * 10 + c - '0';
}
return ret * w;
}
int rd(){
int in;
cin >> in;
return in;
}
void write(int x){
if(x < 0){
putchar('-');
x = -x;
}
if(x > 9){
write(x / 10);
}
putchar(x % 10 + '0');
}
const int MAXN = 2e3 + 5, MAXM = 2e5 + 5, INF = 1e9 + 5, MOD = 1e9 + 7;
const ll LINF = 1e18 + 5;
const ld ep = 1e-8, Pi = acos(-1.0);
int n, m, k, x;
int cs, cf;
int a[MAXN];
string s;
ll dp[MAXN][1005][2];
ll dfs(int cur, int stat, bool dir){
if(stat == (1 << n) - 1) return cur == cf;
if(dp[cur][stat][dir]) return dp[cur][stat][dir];
ll ret = 0;
if(dir){
for(int i = 0; i < cur; ++i){
if(!((1 << i) & stat)){
ret += dfs(i, stat | (1 << i), dir ^ 1);
ret %= MOD;
}
}
}
else{
for(int i = cur + 1; i < n; ++i){
if(!((1 << i) & stat)){
ret += dfs(i, stat | (1 << i), dir ^ 1);
ret %= MOD;
}
}
}
return dp[cur][stat][dir] = ret;
}
void clear(){
}
int main(){
cio;
cin >> n >> cs >> cf;
--cs;
--cf;
cout << (dfs(cs, 1 << (cs), 0) + dfs(cs, 1 << (cs), 1)) % MOD;
return 0;
}
