void setup() {
  // put your setup code here, to run once:

pinMode(11, OUTPUT);
pinMode(10, OUTPUT);
pinMode(9, OUTPUT);
}

void loop() {
  // put your main code here, to run repeatedly:

analogWrite(11, random(0, 256));
analogWrite(10, random(0, 256));
analogWrite(9, random(0, 256));
delay(500);

analogWrite(11, 0);
analogWrite(10, 0);
analogWrite(9, 0);
}