Answer
First five terms are $0,3,8,15,24$
Work Step by Step
Given,
$a_{n} = n^{2} -1$
Substituting $n=1,2,3,4,5$ we get,
$a_{1} = 1^{2} -1 = 1 - 1 = 0$
$a_{2} = 2^{2} -1 = 4 - 1 = 3$
$a_{3} = 3^{2} -1 = 9 - 1 = 8$
$a_{4} = 4^{2} -1 = 16 - 1 = 15$
$a_{5} = 5^{2} -1 = 25 - 1 = 24$
First five terms are $0,3,8,15,24$