A Recursion Formula and the Initial Term(s) of a Sequence $$a _ { 1 } = 1 , a _ { 2 } = 3 , a _ { n + 2 } = a _ { n + 1 } - a _ { n }$$

Multiple Choice

A recursion formula and the initial term(s) of a sequence are given. Write out the first five terms of the sequence.
- $$a _ { 1 } = 1 , a _ { 2 } = 3 , a _ { n + 2 } = a _ { n + 1 } - a _ { n }$$

A) $1,3,2,1,0$
B) $1 , - 1,2 , - 3,5$
C) $1,3,2 , - 1 , - 3$
D) $1 , - 3,4 , - 5,6$