11 14 14 17 17 20 20

Two patterns alternate here. The first pattern begins with 10 and adds 2 to each number to arrive at the next; the alternating pattern begins with 34 and subtracts 3 each time.

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.

Here, there are two alternating patterns. The first begins with 17 and adds 2; the second begins with 32 and subtracts 3.

Here, there are two alternating patterns, one addition and one subtraction. The first starts with 2 and increases by 2; the second starts with 44 and decreases by 3.

Here, every third number follows a different pattern from the main series. In the main series, beginning with 16, 10 is added to each number to arrive at the next. In the alternating series, beginning with 56, 12 is added to each number to arrive at the next.

The letters decrease by 1; the numbers are multiplied by 2.

This is an alternating division and addition series: First, divide by 2, and then add 8.

This is a simple addition series; each number is 3 more than the previous number.

In this series, 5 is added to the previous number; the number 70 is inserted as every third number.

This is a simple alternating addition and subtraction series. The first series begins with 8 and adds 3; the second begins with 43 and subtracts 2.