Determine a recursive formula for the sequence: 2, 5, 10, 17,......

1 answer

an = n ^ 2 + 1

n = 1

a1 = 1 ^ 2 + 1 = 1 + 1 = 2

n = 2

a2 = 2 ^ 2 + 1 = 4 + 1 = 5

n = 3

a3 = 3 ^ 2 + 1 = 9 + 1 = 10

n = 4

a4 = 4 ^ 2 + 1 = 16 + 1 = 17