const int pins[] = {2,3,4,5,6,7,8,9,10,11};

void setup() {
  // put your setup code here, to run once:
  for(int i=0;i<(sizeof(pins))/4;i++)
  {
    pinMode(pins[i], OUTPUT);
  }
}

int counter = 0;

void loop() {
  for(int i=0;i<(sizeof(pins))/4;i++)
    digitalWrite(pins[i], bitRead(counter, i) ? HIGH : LOW);

  counter++;
  delay(500);
}