#pragma GCC optimize("Ofast,unroll-loops,O3")
#include <bits/stdc++.h>
using namespace std;
#ifdef LOCAL
#include "algo/debug.h"
#else
#define debug(...) 42
#endif
using int64 = int64_t;
using ld = long double;
using uint64 = uint64_t;
using int128 = __int128_t;
#define all(v) (v).begin(), (v).end()
#define rall(v) (v).rbegin(), (v).rend()
const int md = 1e9 + 7;
const int64 inf = 1e18;
int main() {
ios_base::sync_with_stdio(false);
cin.tie(nullptr);
cout.tie(nullptr);
int n, cs, cf;
cin >> n >> cs >> cf;
vector<vector<vector<vector<int>>>> dp(n + 1, vector<vector<vector<int>>>(n + 1, vector<vector<int>>(n + 1, vector<int>(2, 0))));
dp[2][1][2][0] = 1;
dp[2][2][1][1] = 1;
for (int l = 3; l <= n; l++) {
for (int s = 1; s <= l; s++) {
for (int f = 1; f <= l; f++) {
if (s == f) continue;
for (int w = 0; w < 2; w++) {
if (w == 0) {
for (int k = s; k < l; k++) {
dp[l][s][f][0] = (dp[l][s][f][0] + dp[l - 1][k][f - int(f > s)][1]) % md;
}
} else {
for (int k = 1; k < s; k++) {
dp[l][s][f][1] = (dp[l][s][f][1] + dp[l - 1][k][f - int(f > s)][0]) % md;
}
}
}
}
}
}
cout << (dp[n][cs][cf][0] + dp[n][cs][cf][1]) % md << '\n';
return 0;
}
