JSFiddle - React, Tailwind, and code Playground

JavaScript

function randomBetween (min, max) {
  var ceiling = max + 1;
  return Math.floor(Math.random() * (ceiling - min)) + min;
}

function randomBetweenAndExcluding (min, max, array) {
  var random;
  do {
    random = randomBetween(min, max);
  } while(array.includes(random));
  return random;
}

array = [1,2,5];
alert(randomBetweenAndExcluding(1,5,array))