Chapter 11 - Further Topics in Algebra - 11.2 Arithmetic Sequences and Series - 11.2 Exercises - Page 1024: 19

$a_{1}=5;$ $a_{2}=3;$ $a_{3}=1;$ $a_{4}=-1;$ $a_{5}=-3$

$a_{1}=5;d=-2$ $a_{2}=a_{1}+d=5+\left( -2\right) =3;$ $a_{3}=a_{2}+d=3+\left( -2\right) =1;$ $a_{4}=a_{3}+d=1+\left( -2\right) =-1;$ $a_{5}=a_{4}+d=\left( -1\right) +\left( -2\right) =-3$