JSFiddle - React, Tailwind, and code Playground

JavaScript

$(document).ready(function(){
    var $myTable = $("<table></table>");
    var $myRow;
    var rowCount = 10; //or whatever you want
    var cellCount = 1;
    var i = 0;
    for (i=0; i<rowCount; i++){
        $myRow = $("<tr></tr>");
        cellCount = (i%2 === 0)? 3 : 1;
    
        for (var j=0; j<cellCount; j++){
           $myRow.append("<td>a</td>") 
        }
    
        $myTable.append($myRow);
    }
    
    $("body").append($myTable); //if you want to add it to your document.
});