int led1 = 1;
int led2 = 2;
int led3 = 3;
void setup() {
pinMode (led1, OUTPUT);
pinMode (led2, OUTPUT);
pinMode (led3, OUTPUT);
}
void loop()
{
digitalWrite (led1, HIGH);
delay (500);
digitalWrite (led1, LOW);
delay (1600);
digitalWrite(led2, HIGH);
delay(700);
digitalWrite(led2, LOW);
delay(1400);
digitalWrite(led3, HIGH);
delay(900);
digitalWrite(led3, LOW);
delay(1200);
}