The sequence $a _ { n }$ is defined by the rule: $$a _ { n } = ( - 1 ) ^ { n } - ( - 1 ) ^ { n - 1 } + ( - 1 ) ^ { n + 2 } \text { for } n \geq 1$$ Find the value of $$\sum _ { n = 1 } ^ { 39 } a _ { n }$$ A - 39 B - 3 C - 1 D 0 E 1 F 3 G 39
& B & 4 & C
The sequence $a _ { n }$ is defined by the rule:
$$a _ { n } = ( - 1 ) ^ { n } - ( - 1 ) ^ { n - 1 } + ( - 1 ) ^ { n + 2 } \text { for } n \geq 1$$
Find the value of
$$\sum _ { n = 1 } ^ { 39 } a _ { n }$$
A - 39
B - 3
C - 1
D 0
E 1
F 3
G 39