Write the first ten terms of a sequence whose first term is -10 and whose common difference is -2

The question tackles about arithmetic sequence.
Arithmetic sequence has the formula:
an = a1 + (n – 1)d.
where 
an = number at nth term
a1 = 1st term
n = number of terms
d = common difference.

an = a1 + (n – 1)d.
a1 = -10
d = -2
n = 10

a2 = -10 + (2-1) -2
a2 = -12

if we continue until a10, the sequence will be
-10, -12, -14, -16, -18, -20, -22, -24, -26, -30