## Algebra and Trigonometry 10th Edition

$a_n=n^2-1$
$a_1=0=1^2-1$ $a_2=3=2^2-1$ $a_3=8=3^2-1$ $a_4=15=4^2-1$ $a_5=24=5^2-1$ Each term is 1 less than the square of $n$: $a_n=n^2-1$