int leds[13] = {1,2,3,4,5,6,7};

void setup() 
{
  for (int i=0;i<7;i++){
    pinMode(leds[i], OUTPUT);
}
}
void loop() {
digitalWrite(1, HIGH); 
digitalWrite(2, HIGH); 
digitalWrite(3, HIGH); 
digitalWrite(4, HIGH);
digitalWrite(5, HIGH); 
digitalWrite(6, HIGH); 
digitalWrite(7, HIGH); 
}