Lightning Flash Controller

/*Flash controller for 3 LEDs used on Thunder And Lighting Control Board
This sketch created and copywrite by Gary C. Granai https://www.facebook.com/gary.granai and is included in the
  Arduino For Model Railing Library at https://steamtraininfo.com/arduino-projects
  You are free to use this sketch and amend it for your own personal use as long as these credits remain intact.   Using it in any manner or form for commercial purposes is prohibited.*/

#define toggle A0
int val=0;

int randNumber;
void setup() {
  pinMode(A0, INPUT);
/* This sets 3 leds on pins D4 to D6 to output */
  for (int i = 4; i <= 7; i++) {
    pinMode(i, OUTPUT); // sets pins to output
  }
  randomSeed(analogRead(A7)); /*sets the pin to create "static so the the initial LED to light is different
  eacg time through the loop  */
}

//***************************************************
void loop() {
  BlinkRandomly();
}

//**************************************************
void BlinkRandomly() {
  val=analogRead(toggle);
  if(val>750){
  randNumber= random(20, 30);
  int LightLED = random(4, 7); //randomly selects LED to light.  Must use +1 over the last pin number
  //(ie: 6 + 1 = 7)
  int dlay =  randNumber; // sets the blink rate in milliseconds
  digitalWrite(LightLED, HIGH);
  delay(dlay);
  digitalWrite(LightLED, LOW);
  delay(dlay);
  }
}