Need some help with LED binary counter, not sure if it's hardware or software

Projects General Guidance
7

Fix your code to turn them off briefly also:

unsigned long nextinterval = 0;
void setup() {                
  // initialize the digital pin as an output.
  // Pin 13 has an LED connected on most Arduino boards:
  pinMode(5, OUTPUT);
  pinMode(4, OUTPUT);  
  pinMode(3, OUTPUT);  
  pinMode(2, OUTPUT);

}

void loop() {
if (millis()>= nextinterval){
nextinterval=nextinterval+1000;
 digitalWrite(5, HIGH);
 digitalWrite(4, HIGH);
 digitalWrite(3, HIGH);
 digitalWrite(2, HIGH);
 delay(490);
 digitalWrite(5, LOW);
 digitalWrite(4, LOW);
 digitalWrite(3, LOW);
 digitalWrite(2, LOW);
 }
 }