(i) 2, 4, 8, 16, . . .
(ii) 2, 5/2 , 3, 7/2. . .
(iii) – 1.2, – 3.2, – 5.2, – 7.2, . . .
(iv) – 10, – 6, – 2, 2, . . .
(v) 0.2, 0.22, 0.222, 0.2222, . . .
(vi) 0, – 4, – 8, –12, . . .
(vii) 1, 3, 9, 27, . . .
(ix) a, 2a, 3a, 4a, . . .
(xi) a, a2, a3, a4, . . .
(xiv) 12, 32, 52, 72, . . .
(xv) 12, 52, 72, 73, . . .