var rainbowCounter = 0;
    var size = 24;
    var rainbowColourArray = new Array(size);


    for (var i = 0; i < size; i++) {
    var red = sin_to_hex(i, 0 * Math.PI * 2 / 3); // 0   deg
    var blue = sin_to_hex(i, 1 * Math.PI * 2 / 3); // 120 deg
    var green = sin_to_hex(i, 2 * Math.PI * 2 / 3); // 240 deg
    rainbowColourArray[i] = "#" + red + green + blue;
    }


    function sin_to_hex(i, phase) {
        var sin = Math.sin(Math.PI / size * 2 * i + phase);
        var int = Math.floor(sin * 127) + 128;
        var hex = int.toString(16);
        return hex.length === 1 ? "0" + hex : hex;
    }