Help! Trying to modify Sketch

Corrected, though im not sure this is what you wanted. Still, its an example of how to implement it. Hope it helps to get the logic of it, so u can implement it to suit you.

int ledPins[] = {
  2, 5, 9, 13 };       // an array of pin numbers to which LEDs are attached
int pinCount = 4;           // the number of pins (i.e. the length of the array)
// Variables will change:
int ledState = LOW;             // ledState used to set the LED
long previousMillis = 0;        // will store last time LED was updated
// the follow variables is a long because the time, measured in miliseconds,
// will quickly become a bigger number than can be stored in an int.
long interval = 1000;       

void setup() {
  // initialize serial communication at 9600 bits per second:
  Serial.begin(9600);
  // make the pushbutton's pin an input:
}


void loop() {
  // loop from the lowest pin to the highest:
  // check to see if it's time to blink the LED; that is, if the 
  // difference between the current time and last time you blinked 
  // the LED is bigger than the interval at which you want to 
  // blink the LED.
  unsigned long currentMillis = millis();
  if(currentMillis - previousMillis > interval) {
    // save the last time you blinked the LED 
    previousMillis = currentMillis;   
    // if the LED is off turn it on and vice-versa:
    if (ledState == LOW)
      ledState = HIGH;
    else
      ledState = LOW;
  }
  int thisPin;
  // the array elements are numbered from 0 to (pinCount - 1).
  // use a for loop to initialize each pin as an output:
  for (int thisPin = 0; thisPin < pinCount; thisPin++)  {
    pinMode(ledPins[thisPin], OUTPUT);  
    digitalWrite(ledPins[thisPin], ledState);
    Serial.println(ledState);  
  }
}