Here is another section I am having trouble with, it asks for:

the sum of the squares of the integers n: -12 less than or equal to n less than or equal 12.

the sum of the reciprocals of the integers n, where 100 less than or equal to n than or equal 200.

the sum of the cubes of the reciprocals of all integers, n where 1 is less than or equal to 50.

Am I supposed to put this in sigma notation or in a sum of a series?

I would appreciate it if you coud point me in the right direction.

Thank you!

Keith Stevens