Just want to verify my answers, if there are wrong answers then plz help me.

1) Give the first 4 terms of the following sequences

(indices begin at 0; you need not multiply everything out):

a) {An} = (-2)^n

b) {An} = 3

c) {An} = 7 + 4^n

d) {An} = 2^n + (-2)^n

My answers:

a) 1,-2,4,-8

b) 3

c) 1,11,23,71

d) 2,0,8,0