import java.io.IOException;
import java.io.InputStream;
import java.io.PrintWriter;

import java.util.NoSuchElementException;

public class Main{
	static FastScanner sc = new FastScanner();
	static PrintWriter out = new PrintWriter(System.out);
	static int n;
	static int mod = 1_000_000_007;
	//static HashMap <String, Integer> map;
	
	public static void main(String[] args) {
		n = sc.nextInt();
		
		int lim = n/3;
		
		if (n<3)
			out.println(0);
		
		else {
			long ans = 0;
			for (int i=1; i<=lim; i++) {
				int l = n-i*3;
				ans+=nCr(i+l-1, i-1);
				ans%=mod;
			}
			
			out.println(ans);
		}
		 
		
		out.flush();
		
	}
	
	
	public static long factorial(int j, int lim) {
		long tmp = 1;
		for (int i=j; i>lim; i--) {
			tmp = (tmp*i)%mod;
		}
		return tmp;
	}
	
	public static long pow (long a, long j) {
	    long res=1;
	    
	    if (a==0)
	    	return 0;
	    
	    if (a==1)
	    	return 1;
	    
	    while (j>0) {
	        if ((j-j/2*2)==1) {
	            res=(res*a)%mod;
	        }
	        a=(a*a)%mod;
	        j>>=1;
	    }
	    return res;
	}
 
	public static long modinv(long j) {
		return pow(j, mod-2);
	}
 
	public static long nCr(int j, int r) {
		int lim = Math.max(j-r, r);
		int min = Math.min(j-r, r);
		
		return factorial(j, lim) * modinv(factorial(min, 0)) % mod ;
	}
	
	
	static class FastScanner {
	    private final InputStream in = System.in;
	    private final byte[] buffer = new byte[1024];
	    private int ptr = 0;
	    private int buflen = 0;

	    private boolean hasNextByte() {
	      if (ptr < buflen) {
	        return true;
	      } else {
	        ptr = 0;
	        try {
	          buflen = in.read(buffer);
	        } catch (IOException e) {
	          e.printStackTrace();
	        }
	        if (buflen <= 0) {
	          return false;
	        }
	      }
	      return true;
	    }

	    private int readByte() {
	      if (hasNextByte()) return buffer[ptr++];
	      else return -1;
	    }

	    private static boolean isPrintableChar(int c) {
	      return 33 <= c && c <= 126;
	    }

	    private void skipUnprintable() {
	      while (hasNextByte() && !isPrintableChar(buffer[ptr])) ptr++;
	    }

	    public boolean hasNext() {
	      skipUnprintable();
	      return hasNextByte();
	    }

	    public String next() {
	      if (!hasNext()) throw new NoSuchElementException();
	      StringBuilder sb = new StringBuilder();
	      int b = readByte();
	      while (isPrintableChar(b)) {
	        sb.appendCodePoint(b);
	        b = readByte();
	      }
	      return sb.toString();
	    }
	    
	    public double nextDouble () {
	    	return Double.parseDouble(next());
	    }

	    public long nextLong() {
	      if (!hasNext()) throw new NoSuchElementException();
	      long n = 0;
	      boolean minus = false;
	      int b = readByte();
	      if (b == '-') {
	        minus = true;
	        b = readByte();
	      }
	      if (b < '0' || '9' < b) {
	        throw new NumberFormatException();
	      }
	      while (true) {
	        if ('0' <= b && b <= '9') {
	          n *= 10;
	          n += b - '0';
	        } else if (b == -1 || !isPrintableChar(b)) {
	          return minus ? -n : n;
	        } else {
	          throw new NumberFormatException();
	        }
	        b = readByte();
	      }
	    }

	    public int nextInt() {
	      return (int) nextLong();
	    }

	    public int[] nextIntArray(int N, boolean oneBased) {
	      if (oneBased) {
	        int[] array = new int[N + 1];
	        for (int i = 1; i <= N; i++) {
	          array[i] = sc.nextInt();
	        }
	        return array;
	      } else {
	        int[] array = new int[N];
	        for (int i = 0; i < N; i++) {
	          array[i] = sc.nextInt();
	        }
	        return array;
	      }
	    }

	    public long[] nextLongArray(int N, boolean oneBased) {
	      if (oneBased) {
	        long[] array = new long[N + 1];
	        for (int i = 1; i <= N; i++) {
	          array[i] = sc.nextLong();
	        }
	        return array;
	      } else {
	        long[] array = new long[N];
	        for (int i = 0; i < N; i++) {
	          array[i] = sc.nextLong();
	        }
	        return array;
	      }
	    }
	    
	    public double [] nextDoubleArray(int N, boolean oneBased) {
		      if (oneBased) {
		        double [] array = new double[N + 1];
		        for (int i = 1; i <= N; i++) {
		          array[i] = sc.nextDouble();
		        }
		        return array;
		      } else {
		        double[] array = new double[N];
		        for (int i = 0; i < N; i++) {
		          array[i] = sc.nextDouble();
		        }
		        return array;
		      }
		    }
		  
	  }
	
	
}


Measured memory_bytes: 32588