#include<iostream>
#include<cstdio>
#include<algorithm>
using namespace std;
const int N = 3010;
const int MOD = 1000000007;
int maxt,maxd,maxm;
int f[N][N/2];
bool issafe(int t,int m){
    return (t-2*m) < maxd;
}

int main(){
    cin>>maxd>>maxt>>maxm;
    f[0][0] = 1;
    for(int i = 0; i <= maxt ;i++){
        for(int j = 0; j<=i && j<=maxm; j++){
            if(((j-1)>=0) && issafe(i-1,j-1)) f[i][j]=(f[i][j]+f[i-1][j-1])%MOD;
            if((j<=i-1) && issafe(i-1,j)) f[i][j] = (f[i][j]+f[i-1][j])%MOD;
        }
    }
    cout<<f[maxt][maxm];
    return 0;
}