import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.nio.charset.Charset;
import java.util.regex.Pattern;

public class Solution {
  private static final int MODULO = 1000000007; 
  
  private static long [] readData() {
    try {
      final StringBuilder lines = new StringBuilder();
      final BufferedReader br = new BufferedReader(new InputStreamReader(System.in, Charset.forName("UTF-8")));
      for (String line=null; null != (line = br.readLine()); ) {
        line = line.trim();
        if (!line.isEmpty()) {
          lines.append(line).append(" ");
        }
      }
      return Pattern.compile("\\s+").splitAsStream(lines.toString()).mapToLong(Long::parseLong).toArray();
    }
    catch (IOException e) {
      throw new RuntimeException(e);
    }
  }
  
  private static void assertSize(long [] data, int size) {
    if (size != data.length) {
      throw new IllegalArgumentException(String.format("expected %d elements, got: %d", size, data.length));
    }
  }
  
  public static int virus(long [] data){
    assertSize(data, 3);
    final long a = data[0];
    final long b = data[1];
    final long t = data[2];
    long virus = 1;
    for (int i=0; i < t; i++) {
      virus = Math.round(0.5 * a * virus + 0.5 * b * virus);
    }
    return (int) (virus % MODULO);
  }

  public static void main(String[] args) {
    System.out.println(virus(readData()));
  }
}