JSFiddle - React, Tailwind, and code Playground

by Preachieved

HTML

seed:<input id="seed" type="text" value="1"></input><br/>
depth:<input id="depth" type="number" value="5"></input><br/>
<button onclick="go()">Go</button>
<div id="stdout"></div>

CSS

#stdout{
    border: 1px solid black;
}

JavaScript

window.go = function go(){
    var num = $("#seed").val();
    var out = $("#stdout").html("");
    for(var i=0;i<$("#depth").val();i++){
        out.html(out.html()+num+"<br/>");
        var newnum = "";
        var numarr = num.match(/(\d)\1*/img);
        for (match in numarr){
            newnum += numarr[match].length + numarr[match].substring(0,1);
        }
        num = newnum;
    }
}