import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.HashMap;
import java.util.HashSet;
import java.util.LinkedList;
import java.util.Scanner;
import java.util.Set;

public class Main {
	
	public static final long MOD = 1000000007;
	
	public static long dfs(final int N, final int rest, final int K, final int prev, ArrayList<HashMap<Integer, HashMap<Integer, Long>>> memoized){
		final int use_limit = prev + K;
		
		if(memoized.get(N).containsKey(rest) && memoized.get(N).get(rest).containsKey(prev)){
			return memoized.get(N).get(rest).get(prev);
		}
		
		if(N == 0){ return rest == 0 ? 1 : 0; }
		else if(rest <= 0){ return 0; }
		
		final int lowest = N * use_limit + N * (N - 1) / 2 * K;
		//System.out.println(lowest);
		if(lowest > rest){ 
			if(!memoized.get(N).containsKey(rest)){ memoized.get(N).put(rest, new HashMap<Integer, Long>()); }
			memoized.get(N).get(rest).put(prev, 0l);
			return 0;
		}
		//System.out.println(N + " " + use_limit + " " + rest + " " + lowest + " " + (rest - lowest + N - 1) / N);
		
		long ret = 0;
		for(int use = use_limit + (rest - lowest + N - 1) / N; use >= use_limit; use--){
			//System.out.println(use);
			ret += dfs(N - 1, rest - use, K, use, memoized);
			ret %= MOD;
		}
		
		if(!memoized.get(N).containsKey(rest)){
			memoized.get(N).put(rest, new HashMap<Integer, Long>());
		}
		memoized.get(N).get(rest).put(prev, ret);
		
		return ret;
	}
	
	public static void main(String[] args){
		Scanner sc = new Scanner(System.in);
		
		final int N = sc.nextInt();
		final int S = sc.nextInt();
		final int K = sc.nextInt();
		
		ArrayList<HashMap<Integer, HashMap<Integer, Long>>> memoized = new ArrayList<HashMap<Integer, HashMap<Integer, Long>>>();
		for(int i = 0; i <= N; i++){
			memoized.add(new HashMap<Integer, HashMap<Integer, Long>>());
		}
		
		System.out.println(dfs(N, S, K, -K, memoized));
		
		//System.out.println(memoized);
	}
	
}