What is the sum of the series?

4+12+36+108 + ... + 8748

8908

10,204

13,120

17,816

4 + 12 + 36 ... etc

is a sum that can be rewritten in form

4 (1, 3, 9, 27, 81, etc) this can further be written in sigma notation:

4 Sigma [ 3 ^ (i - 1) ]

The sum of the indefinite summation will be the limit as i goes to infinity = infinity