// Define LED pin
int ledPin = 4;

// Setup runs once when you press reset or power the board
void setup() {
  // Initialize the digital pin as an output.
  pinMode(ledPin, OUTPUT);
}

// Main loop
void loop() {
  digitalWrite(ledPin, HIGH);  
  delay(1000);                 
  digitalWrite(ledPin, LOW);   
  delay(1000);          
  digitalWrite(ledPin, HIGH);  
  delay(555);                 
  digitalWrite(ledPin, LOW);   
  delay(1000);  
}