using System; using System.Collections; using System.Collections.Generic; using System.Diagnostics; using System.Globalization; using System.IO; using System.Text; using System.Linq; using E = System.Linq.Enumerable; internal partial class Solver { public void Run() { var N = ni(); var d = ni(); var K = ni(); var dp = new long[K + 1]; int mod = 1000000007; dp[0] = 1; for (int _ = 0; _ < N; _++) { int cur = K; long sum = 0; for (int i = K; i >= 0; i--) { while (cur >= 0 && i - cur <= d) { sum += dp[cur]; cur--; } sum -= dp[i]; dp[i] = sum; dp[i] %= mod; } } cout.WriteLine(dp[K] % mod); } } // PREWRITEN CODE BEGINS FROM HERE internal partial class Solver : Scanner { public static void Main(string[] args) { #if LOCAL byte[] inputBuffer = new byte[1000000]; var inputStream = Console.OpenStandardInput(inputBuffer.Length); using (var reader = new StreamReader(inputStream, Console.InputEncoding, false, inputBuffer.Length)) { Console.SetIn(reader); new Solver(Console.In, Console.Out).Run(); } #else Console.SetOut(new StreamWriter(Console.OpenStandardOutput()) { AutoFlush = false }); new Solver(Console.In, Console.Out).Run(); Console.Out.Flush(); #endif } #pragma warning disable IDE0052 private readonly TextReader cin; private readonly TextWriter cout; #pragma warning restore IDE0052 public Solver(TextReader reader, TextWriter writer) : base(reader) { cin = reader; cout = writer; } public Solver(string input, TextWriter writer) : this(new StringReader(input), writer) { } #pragma warning disable IDE1006 #pragma warning disable IDE0051 private int ni() { return NextInt(); } private int[] ni(int n) { return NextIntArray(n); } private long nl() { return NextLong(); } private long[] nl(int n) { return NextLongArray(n); } private double nd() { return NextDouble(); } private double[] nd(int n) { return NextDoubleArray(n); } private string ns() { return Next(); } private string[] ns(int n) { return NextArray(n); } #pragma warning restore IDE1006 #pragma warning restore IDE0051 } internal static class LinqPadExtension { [Conditional("DEBUG")] public static void Dump(this T obj) { #if DEBUG LINQPad.Extensions.Dump(obj); #endif } } public class Scanner { private readonly TextReader Reader; private readonly CultureInfo ci = CultureInfo.InvariantCulture; private readonly char[] buffer = new char[2 * 1024]; private int cursor = 0, length = 0; private string Token; private readonly StringBuilder sb = new StringBuilder(1024); public Scanner() : this(Console.In) { } public Scanner(TextReader reader) { Reader = reader; } public int NextInt() { return checked((int)NextLong()); } public long NextLong() { var s = Next(); long r = 0; int i = 0; bool negative = false; if (s[i] == '-') { negative = true; i++; } for (; i < s.Length; i++) { r = r * 10 + (s[i] - '0'); #if DEBUG if (!char.IsDigit(s[i])) throw new FormatException(); #endif } return negative ? -r : r; } public double NextDouble() { return double.Parse(Next(), ci); } public string[] NextArray(int size) { string[] array = new string[size]; for (int i = 0; i < size; i++) { array[i] = Next(); } return array; } public int[] NextIntArray(int size) { int[] array = new int[size]; for (int i = 0; i < size; i++) { array[i] = NextInt(); } return array; } public long[] NextLongArray(int size) { long[] array = new long[size]; for (int i = 0; i < size; i++) { array[i] = NextLong(); } return array; } public double[] NextDoubleArray(int size) { double[] array = new double[size]; for (int i = 0; i < size; i++) { array[i] = NextDouble(); } return array; } public string Next() { if (Token == null) { if (!StockToken()) { throw new InvalidOperationException(); } } var token = Token; Token = null; return token; } public bool HasNext() { if (Token != null) { return true; } return StockToken(); } private bool StockToken() { while (true) { sb.Clear(); while (true) { if (cursor >= length) { cursor = 0; if ((length = Reader.Read(buffer, 0, buffer.Length)) <= 0) { break; } } var c = buffer[cursor++]; if (33 <= c && c <= 126) { sb.Append(c); } else { if (sb.Length > 0) break; } } if (sb.Length > 0) { Token = sb.ToString(); return true; } return false; } } }