!!!!!!!! 50 POINTS !!!!!!!!What are the explicit equation and domain for a geometric sequence with a first term of 2 and a second term of βˆ’8?

an = 2(βˆ’8)^(n βˆ’ 1); all integers where n β‰₯ 1
an = 2(βˆ’8)^(n βˆ’ 1); all integers where n β‰₯ 0
an = 2(βˆ’4)^(n βˆ’ 1); all integers where n β‰₯ 0
an = 2(βˆ’4)^(n βˆ’ 1); all integers where n β‰₯ 1