Onsider the arithmetic series: 1 + 9 + 17 + 25 + write a formula for the sum of the first n terms in this series.

We can see this is a summation of multiples of 8 plus 1, which starts at 1.

This can be written in the following way:


Lets verify the summation expression by doing the sequence for the first 4 elements (hence , as it starts from 0):



As you can see, the generalization is correct.

Dbc if u do the math and stuff that what i got let me know if i was wrong