In this task you will be given a list of integers. You should only return an integer if the first digit is the same as the last digit in the number. If an integer has a single digit, then it should be returned. If there are no integers that start and end with the same digit then an empty list ("[]") should be returned.
[-597, 844, 714, 608, 251, 428, -507, 312, -525, -680, -589, -265, -634, 612, 157]