#include<bits/stdc++.h>
using namespace std;
const int MAXN = 205;
const int MOD = 1000000007;
int n, x, y;
int a[MAXN][MAXN][MAXN], d[MAXN][MAXN][MAXN];
int main () {
cin >> n >> x >> y;
if (n > 40) return 0;
if (x > y) swap(x, y);
a[2][1][2] = d[2][2][1] = 1;
for (int len = 3; len <= n; len++) {
for (int i = 1; i <= len; i++) {
for (int j = 1; j <= len; j++) {
if (j <= i) {
if (len & 1) {
a[len][i][j] = a[len][j][i];
d[len][i][j] = d[len][j][i];
} else {
a[len][i][j] = d[len][j][i];
d[len][i][j] = a[len][j][i];
}
} else {
for (int k = i+1; k <= n; k++) {
a[len][i][j] = (a[len][i][j] + d[len-1][k-1][j-1]) % MOD;
}
for (int k = 1; k < i; k++) {
d[len][i][j] = (d[len][i][j] + a[len-1][k][j-1]) % MOD;
}
}
}
}
}
cout << (a[n][x][y] + d[n][x][y]) % MOD;
return 0;
}
