I have a specific need in my project where I should enable only 1st and the 15th of every month in the jquery date picker. I have seen several solutions that is based on an array of dates, but that is not going to work for me. Is there a way a pattern can be applied?

@mtndesign - For your response/question on why I cannot use an array:
The datepicker should always (all past, current and future months & years) show only 1 or 15. How many dates I can keep in the array? How do I create array by the user behavior for the user selected month? I felt that it will be complicated if I start creating an array