Adding a Sequence in the Form 1 + 3 + .... + 2n - 1

When you have a sequence in the format similar to:

1 + 3 + 5 + 7 + ... + 2n - 1

1) Take the last number presented and add it to 1.

2) Divide the number by 2.

3) Square the number.

You now have the total of the sequence!

Ex: 1 + 3 + 5 + ... + 27

1) 27 + 1 = 28

2) 28/2 = 14

3) 14² = 196

Therefore, 1 + 3 + 5 + ... + 27 = 196

Ex: 1 + 3 + 5 + ... + 55

1) 55 + 1 = 56

2) 56/2 = 28

3) 28² = 784

Now try:
Ex: 1 + 3 + 5 + ... + 15

Ex: 1 + 3 + 5 + ... + 39

Ex: 1 + 3 + 5 + ... + 31