## Algebra 1: Common Core (15th Edition)

$A(n)=19+(n-1)(-1)$
$A(1) =19$, so the first term is 19. $A(n) = A(n - 1) -1$ $A(n)=A(1)+(n-1)d$ $A(n)=19+(n-1)(-1)$ The explicit formula $A(n)=19+(n-1)(-1)$ represents the arithmetic sequence.