int ledPin = D2; 

void setup()
{
    // We want to tell the Argon that we'll use
    // D2 as an output pin.
    pinMode( ledPin, OUTPUT );
    
}

void loop()
{
    // First... On
    for (int i = 0; i < 5; i++) // for loop to enable led's 5 times blink
    {
        digitalWrite( ledPin, HIGH ); // Turn ON the LED pins
        delay( 500 );                 // Wait for 500mS = 0.5 second
       // Now... Off
        digitalWrite( ledPin, LOW ); // Turn OFF the LED pins
        delay( 500 );                // Wait for 500mS = 0.5 second
    }
   // Off and wait for 3 seconds
    digitalWrite( ledPin, LOW ); // Turn OFF the LED pins
    delay( 3000 );               // Wait for 3000mS = 3 second
    // rinse + repeat
}