int ledPin = 3;
//int buttonPin = 2;



void setup() {
 
  pinMode(ledPin,OUTPUT);
  //pinMode(buttonPin, INPUT);

}

void loop() {
      int flick = 0;
      
  while(true)
  {
    while(flick<=300)
    {
      digitalWrite(ledPin, HIGH);
      delay(flick);
      digitalWrite(ledPin, LOW);
      delay(flick);
      flick+=10;
    }
    while(flick>0)
    {
       digitalWrite(ledPin, HIGH);
      delay(flick);
      digitalWrite(ledPin, LOW);
      delay(flick);
      flick-=10;
    }
    
  }
      
    
  }