Show only odd or even bar numbers

I could not see a connection between the title you selected for the question and the end result you are seeking.

Original title: "Show bar number based on number type"

So I updated the title of the question to describe the context as I understand it.

If you want to add a user input and sections of code to enable this to display only odd numbers or only even numbers this is the solution. I have updated the default color so that it will work with the majority of users. Most users will select either a white or black background for their charts so I selected Gray as the default color.

input oddOrEven = {default Odd, Even};
def factor = 2;
def barNumber = 1 + (SecondsFromTime(0930) / 120);
def adjustedBarNumber = if oddOrEven == oddOrEven.Even then
if barNumber % factor == 0 then barNumber else Double.NaN else
if barNumber % factor > 0 then barNumber else Double.NaN;
plot barNum = adjustedBarNumber;
barNum.SetPaintingStrategy(PaintingStrategy.VALUES_BELOW);
barNum.SetDefaultColor(Color.GRAY);