Combinatorial Counting: Painting Streetlight Poles with Color Restrictions

A town has n streetlights running along the north side of main street.
The poles on which they are mounted need to be painted so that they do not rust.

QUESTION:In how many ways may they be painted with red, white, blue, yellow, purple and green if an even number of them are to be painted green?

Clarification: order matters colors can repeat, but you do not have to use all four colors

The answer is accepted.
Join Matchmaticians Affiliate Marketing Program to earn up to 50% commission on every question your affiliated users ask or answer.