In this alternating repetition series, a random number, 33, is interpolated every third number into a simple addition series, in which each number increases by 2.
In this simple subtraction with repetition series, each number is repeated, then 3 is subtracted to give the next number, which is then repeated, and so on.
This is a simple subtraction with repetition series. It begins with 20, which is repeated, then 3 is subtracted, resulting in 17, which is repeated, and so on.
EXAMIANS