int sosLED = 13;
int dms = 0;
int charPause = 500;

void setup() {
  // put your setup code here, to run once:
  pinMode(sosLED, OUTPUT);
}

void loop() {
  // put your main code here, to run repeatedly:
  delay(charPause);
  for(int i = 0; i<3; i++){
    if(i == 1){
      dms = 750;
    }
    else{
      dms = 100;
    }
    for(int i = 0; i<3; i++){
      digitalWrite(sosLED, HIGH);
      delay(dms);  // delay in ms
      digitalWrite(sosLED, LOW);
      delay(dms);  // delay in ms
      // delay(charPause);
    }
    delay(charPause);
  }
}