LED Sequencer

int ledArray[] = {2, 3, 4, 5, 6, 7, 8, 9};

int delayTime = 50;

void setup() {
  //initialise ledArray as outputs
  for (int i = 0; i < 10; i++) {
    pinMode(ledArray[i], OUTPUT);
  }
}

void loop() {
  //turn LEDs on from 0-7
  for (int i = 0; i <= 7; i++) {
    digitalWrite(ledArray[i], HIGH);
    delay(delayTime);
  }

  //turn LEDs off from 7-0
  for (int i = 7; i >= 0; i--) {
    digitalWrite(ledArray[i], LOW);
    delay(delayTime * 2);
  }
}