int led2 = 2;
int led3 = 3;
int led4 = 4;
int led5 = 5;
int led6 = 6;
int led7 = 7;
int led8 = 8;
int led9 = 9;

void setup() {
  // put your setup code here, to run once:
  Serial.begin(9600);
  pinMode(2, OUTPUT);
  pinMode(3, OUTPUT);
  pinMode(4, OUTPUT);
  pinMode(5, OUTPUT);
  pinMode(6, OUTPUT);
  pinMode(7, OUTPUT);
  pinMode(8, OUTPUT);
  pinMode(9, OUTPUT);
}

void loop() {
  // put your main code here, to run repeatedly:
  digitalWrite(2, HIGH);
  Serial.println("The ON LED is 2");
  delay(1000);
  digitalWrite(2, LOW);
  digitalWrite(3, HIGH);
  Serial.println("The ON LED is 3");
  delay(700);
  digitalWrite(3, LOW);
  digitalWrite(4, HIGH);
  Serial.println("The ON LED is 4");
  delay(500);
  digitalWrite(4, LOW);
  digitalWrite(5, HIGH);
  Serial.println("The ON LED is 5");
  delay(300);
  digitalWrite(5, LOW);
  digitalWrite(6, HIGH);
  Serial.println("The ON LED is 6");
  delay(100);
  digitalWrite(6, LOW);
  digitalWrite(7, HIGH);
  Serial.println("The ON LED is 7");
  delay(50);
  digitalWrite(7, LOW);
  digitalWrite(8, HIGH);
  Serial.println("The ON LED is 8");
  delay(25);
  digitalWrite(8, LOW);
  digitalWrite(9, HIGH);
  Serial.println("The ON LED is 9");
  delay(10);
  digitalWrite(9, LOW);
}