int ledRot   = 13;
int ledGelb  = 12;
int ledGruen = 11;
int x =1;                

void setup() {

  pinMode(ledRot, OUTPUT);          
  pinMode(ledGelb, OUTPUT);           
  pinMode(ledGruen, OUTPUT);
}

void loop() {

  digitalWrite(ledRot, LOW);            
  digitalWrite(ledGelb, LOW);           
  digitalWrite(ledGruen, LOW);          

  digitalWrite(ledRot, HIGH);           
  delay(x);

  //x=x*2;

  if (x>1000) {
    x=1;                         
  }

  digitalWrite(ledRot, LOW);           
  digitalWrite(ledGelb, HIGH);         
  delay(x); 

  //x=x*2; 

  //if (x>1000) {
  //  x=1; 
  //}                       

  digitalWrite(ledGelb, LOW);
  digitalWrite(ledGruen, HIGH);
  delay(x);

  //x=x*2;

  //if (x>1000) {
  //  x=1;
  //}

  digitalWrite(ledGruen, LOW);
  digitalWrite(ledGelb, HIGH);
  delay (x);

  x=x*2;

  if (x>1000) {
    x=1;
  }

}