JSFiddle - React, Tailwind, and code Playground

JavaScript

function generatePool (count, luckyNumbers) {
    var arr = [], i, j;
    for (i = 1; i <= count; i++) {
        if (luckyNumbers[i]) {
            for (j = 0; j < luckyNumbers[i]; j++) {
                arr.push(i);
            }
        } else {
            arr.push(i);
        }
    }
    return arr;
}

function randomNumber (pool) {
    return pool[ Math.floor(Math.random() * pool.length) ];
}

//-- usage

var luckyNumbers = {};
luckyNumbers[13] = 10;
luckyNumbers[25] = 100;

var pool = generatePool(300, luckyNumbers);

alert(randomNumber(pool));