<link href="//maxcdn.bootstrapcdn.com/bootstrap/4.1.1/css/bootstrap.min.css" rel="stylesheet" id="bootstrap-css">
<script src="//maxcdn.bootstrapcdn.com/bootstrap/4.1.1/js/bootstrap.min.js"></script>
<script src="//cdnjs.cloudflare.com/ajax/libs/jquery/3.2.1/jquery.min.js"></script>
<!------ Include the above in your HEAD tag ---------->
<!DOCTYPE html>
<html>
<body>
<button onclick="doit()">doit</button>
<script>
function doit(){
var text="";
for (var i=1;i<=10;i++){
text+="\n";
for (var j=1;j<=i;j++){
text+=1+" "
}
}
console.log(text)
}
</script>
</body>
</html>
