int LED = 13 ;

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

Serial.begin(115200);
for(int a = 99 ; a >= 1 ; a -= 2){
  Serial.print("Reverse ODD Numbers : ");
  Serial.println(a);

  digitalWrite(LED , HIGH);
  delay(800);
  digitalWrite(LED , LOW);
  delay(1500);
}
}

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

}