#include <LiquidCrystal_I2C.h>

LiquidCrystal_I2C LCD = LiquidCrystal_I2C(0x27, 20, 4);


void setup() {
  LCD.init();
  LCD.backlight();  
}

void loop() {
  LCD.clear();
  LCD.setCursor(0, 0);
  LCD.print("1");
  LCD.setCursor(0, 1);
  LCD.print("2"); 
  LCD.setCursor(0, 2);
  LCD.println("3");
  LCD.setCursor(0, 3);
  LCD.println("4");
  delay(1000);
}