int buttonPin = 4;
int ledPin =  3;

int buttonState = 0;

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

void loop() {
  buttonState = digitalRead(buttonPin);
  
  if (buttonState == HIGH) {
    // F
    delay(5000);
    digitalWrite(ledPin, HIGH);
    delay(500);
    digitalWrite(ledPin, LOW);

    delay(500);
    digitalWrite(ledPin, HIGH);
    delay(500);
    digitalWrite(ledPin, LOW);

    delay(500);
    digitalWrite(ledPin, HIGH);
    delay(2000);
    digitalWrite(ledPin, LOW);

    delay(500);
    digitalWrite(ledPin, HIGH);
    delay(500);
    digitalWrite(ledPin, LOW);

    delay(500);
    digitalWrite(ledPin, HIGH);
    delay(500);
    digitalWrite(ledPin, LOW);

    delay(500);
    digitalWrite(ledPin, HIGH);
    delay(2000);
    digitalWrite(ledPin, LOW);

    delay(500);
    digitalWrite(ledPin, HIGH);
    delay(2000);
    digitalWrite(ledPin, LOW);

    delay(500);
    digitalWrite(ledPin, HIGH);
    delay(500);
    digitalWrite(ledPin, LOW);

    delay(500);
    digitalWrite(ledPin, HIGH);
    delay(500);
    digitalWrite(ledPin, LOW);

    delay(500);
    digitalWrite(ledPin, HIGH);
    delay(500);
    digitalWrite(ledPin, LOW);
    
  } else {
    // turn LED off:
    digitalWrite(ledPin, LOW);
  }
}