PLEASE help I don't understand

What are the first five terms of the sequence defined as
a(1)=3
a(n+1)=a(n)-4, for n≥1?

A) -3, -2, -1, 0, 1
B)-1, -5, -9, -13, -17
C) 3, -1, -5, -9, -13
D) 3, -1, 0, 1, 2

2 answers

well, you said the first one was 3
they go down 4 at a time
so
3 , -1 .......
then -1 - 4 = -5
so
3 , -1 , -5 , .... well that is all we need
a2= 3-4= ??
a3= a2-4= ???
a4= a3-4= ....