#include <iostream>
#include <cstring>
#include <vector>
#include <algorithm>
#include <deque>
#include <set>
#include <utility>
#include <array>
#pragma GCC optimize("Ofast,unroll-loops")
#pragma GCC target("avx2,tune=native")
using namespace std;
#define ALL(x) x.begin(), x.end()
#define ShinLena cin.tie(nullptr)->sync_with_stdio(false);
using ll = long long;
#define N 2005
const ll M = 1000000007;
int n, cs, cf, dp[2][N][2][2];
int main()
{
ShinLena;
cin >> n >> cs >> cf;
dp[0][0][0][0] = 1;
for (int I = 1, i = 1; i <= n; ++i, I ^= 1)
{
memset(dp[I], 0, sizeof *dp);
if (i == cs)
{
for (int j = 1; j <= i; ++j)
{
dp[I][j][0][0] = 0;
dp[I][j][1][0] = dp[!I][j][0][0] % M;
dp[I][j][1][1] = (dp[!I][j-1][0][1] + dp[!I][j][0][1]) % M;
}
}
if (i == cf)
{
for (int j = 1; j <= i; ++j)
{
dp[I][j][0][1] = (dp[!I][j-1][0][0] + dp[!I][j][0][0]) % M;
dp[I][j][1][1] = (dp[!I][j-1][1][0] + dp[!I][j][1][0]) % M;
}
}
else
{
for (int j = 1; j <= i; ++j)
{
dp[I][j][0][0] =
((1ll * dp[!I][j+1][0][0] * j) % M
+ (1ll * dp[!I][j-1][0][0] * (j+1) % M)
) % M;
dp[I][j][1][0] =
(
(1ll * dp[!I][j][0][0]) +
(1ll * dp[!I][j+1][1][0] * j) % M
) % M;
dp[I][j][0][1] =
(
(1ll * dp[!I][j][0][0]) +
(1ll * dp[!I][j+1][0][1] * j) % M
) % M;
dp[I][j][1][1] =
(
(1ll * dp[!I][j][0][1] + dp[!I][j][1][0]) % M +
(1ll * dp[!I][j+1][1][1] * j) % M
) % M;
}
}
}
cout << dp[n&1][1][1][1];
return 0;
}
