int latchPin = 4;
int clockPin = 5;
int dataPin = 3;

byte LEDs = 0b00000001; 

int pauza = 500;

void setup() {
  Serial.begin(9600);
  pinMode (latchPin, OUTPUT);
  pinMode (clockPin, OUTPUT);
  pinMode (dataPin, OUTPUT);
}

void loop() {
  digitalWrite (latchPin, LOW);
  shiftOut (dataPin,clockPin,LSBFIRST,LEDs); 
  digitalWrite (latchPin, HIGH);
  delay (pauza);

  LEDs=LEDs*2; // logical left
  //LEDs=LEDs/2; // logical right
}