/*
_____________________.
|____________________| $$\ $$\ $$\ $$\
|____________________| $$ | \__| $$ | $$ |
|____________________| $$$$$$\ $$$$$$\ $$$$$$\ $$$$$$$\ $$$$$$$\ $$$$$$\ $$\ $$$$$$\ $$$$$$$\ $$$$$$\ $$$$$$$\
|____________________| \_$$ _| $$ __$$\ \____$$\ $$ __$$\ $$ _____| $$ __$$\ $$ |$$ __$$\ $$ __$$\\_$$ _| $$ _____|
|____________________| $$ | $$ | \__|$$$$$$$ |$$ | $$ |\$$$$$$\ $$ | \__|$$ |$$ / $$ |$$ | $$ | $$ | \$$$$$$\
$$ |$$\ $$ | $$ __$$ |$$ | $$ | \____$$\ $$ | $$ |$$ | $$ |$$ | $$ | $$ |$$\ \____$$\
\$$$$ |$$ | \$$$$$$$ |$$ | $$ |$$$$$$$ | $$ | $$ |\$$$$$$$ |$$ | $$ | \$$$$ |$$$$$$$ |
へ ♡ \____/ \__| \_______|\__| \__|\_______/ \__| \__| \____$$ |\__| \__| \____/ \_______/
૮ - ՛) $$\ $$ |
/ ⁻ ៸| \$$$$$$ | are human rights :3
乀 (ˍ,ل ل \______/
*/
#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace std;
using namespace __gnu_pbds;
template <typename T>
using ordered_set = tree<T, null_type, less<T>, rb_tree_tag,
tree_order_statistics_node_update>;
template <typename T>
using ordered_multiset = tree<pair<T, long long>, null_type,
less<pair<T, long long>>, rb_tree_tag,
tree_order_statistics_node_update>;
using namespace std;
using namespace __gnu_pbds;
#define ll long long
#define ull unsigned long long
#define ld long double
#define inf (ll)2e18+4
#define pb push_back
#define se second
#define fi first
#define endl '\n'
#define mp make_pair
#define pll pair<ll,ll>
#define kth_smallest find_by_order
#define num_of_smaller order_of_key
#define fori(x) for(ll i=0;i<x;i++)
#define forj(y) for(ll j=0;j<y;j++)
#define fork(z) for(ll k=0;k<z;k++)
#define forl(a) for(ll l=0;l<a;l++)
#define DEBUG
#ifdef DEBUG
#define show(x) cerr<<#x<<" is "<<x<<endl;
#define show2(x,y) cerr<<#x<<" is "<<x<<" "<<#y<<" is "<<y<<endl;
#define show3(x,y,z) cerr<<#x<<" is "<<x<<" "<<#y<<" is "<<y<<" "<<#z<<" is "<<z<<endl;
#define show4(x,y,z,a) cerr<<#x<<" is "<<x<<" "<<#y<<" is "<<y<<" "<<#z<<" is "<<z<<" "<<#a<<" is "<<a<<endl;
#define show_vec(a) for(auto &i:a)cerr<<i<<" ";cerr<<endl;
#define skillissue cerr<<"your code is running\n";
#define getchar_unlocked _getchar_nolock // comment before submission
#else
#define show(x)
#define show2(x,y)
#define show3(x,y,z)
#define show4(x,y,z,a)
#define show_vec(a)
#define skillissue
#endif
/*
inline int readint() {
int x=0; char ch=getchar_unlocked(); bool s=1;
while(ch<'0'||ch>'9'){if(ch=='-')s=0;ch=getchar_unlocked();}
while(ch>='0'&&ch<='9'){x=(x<<3)+(x<<1)+ch-'0';ch=getchar_unlocked();}
return s?x:-x;
}
*/
const ll mod=1e9+7;
const ll maxn=80+4;
unordered_map<ll,ll>mem[maxn][maxn][2];
ll dp(ll l,ll r,bool las,ll temp){
if(temp==0 and (l!=0 or r!=0))return 0;
if(temp==0 and l==0 and r==0)return 1;
if(mem[l][r][las][temp]==-1)return 0;
else if(mem[l][r][las][temp]!=0)return mem[l][r][las][temp];
//show4(l,r,las,temp)
if(las){
ll cnt=0;
for(ll i=1;i<=r;i++){
cnt = (cnt+dp(l+i-1,r-i,0,temp-i+(ll)(temp<0)))%mod;
}
if(cnt==0){
mem[l][r][las][temp]=-1;
return 0;
}else return mem[l][r][las][temp]=cnt%mod;
}else{
ll cnt=0;
for(ll i=1;i<=l;i++){
cnt = (cnt+dp(l-i,r+i-1,1,temp+i-(ll)(temp>0)))%mod;
}
if(cnt==0){
mem[l][r][las][temp]=-1;
return 0;
}else return mem[l][r][las][temp]=cnt%mod;
}
}
int32_t main(){
ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
ll n,s,e;cin>>n>>s>>e;
//show2(dp(s-1,n-s,0,e-s),dp(s-1,n-s,1,e-s))
cout<<(dp(s-1,n-s,0,e-s)+dp(s-1,n-s,1,e-s))%mod;
}
