Exams - Double Rakiya Numbers

/* A "double rakiya number" is an integer that contains a sequence of 2 digits twice (without overlapping).
 For example "23156312" is a "double rakiya number" because it contains "31" twice. Other examples
 of "double rakiya numbers" are: 1212, 3333, 203103, 5210217, 21212121, and 55555. Examples
 of non-"double rakiya numbers" are: 333, 5, 111222, 1234567131, and 12213114.
 Write a JavaScript function that takes as input two numbers (start and end) and prints at the console
 a HTML list holding all numbers in the range [start…end], along with a link to view details about
 all "double-rakiya numbers" in that range. */

"use strict";

function printHTMLnumberList(arr) {
    var start = Number(args[0]);
    var end = Number(args[1]);

    function checkRepeatingTwoDigits(number) {
        if (number > 1009) {
            var numStr = number.toString(10);
            for (var i = 0; i + 3 < numStr.length; i += 1) {
                for (var j = i + 2; j + 1 < numStr.length; j += 1) {
                    if (numStr[j] == numStr[i] && numStr[j + 1] == numStr[i + 1]) {
                        return true;
                    }
                }
            }
        }
        return false;
    }

    args[0] = '<ul>';
    var index = 1;
    for (var i = start; i <= end; i += 1) {
        args[index] = "<li><span class=";
        var klass = "'num'>";
        var href = '';
        if (checkRepeatingTwoDigits(i)) {
            klass = "'rakiya'>";
            href = '<a href="view.php?id=' + i + '>View</a>';
        }

        args[index] += klass + i + "</span>" + href + "</li>";
        index++;
    }

    args[index] = "</ul>";
    console.log(args.join('\n'));
}

printHTMLnumberList(['5', '8']);
printHTMLnumberList(['11210', '11215']);
printHTMLnumberList(['55555', '55560']);