Look at this sequence: 53, 53, 40, 40, 27, 27, ... What number should come next?

Look at this sequence: 53, 53, 40, 40, 27, 27, ... What number should come next?

This looks like a sequence where we subtract 13 and then 0, 13 and then 0 from the prior number.
Since the last group of 27 repeated, our next number is found by subtracting 13:
27 - 13 = 14