Arithmetic Sequence using recursive definition

Question

an=an-1+d d=4 using the recursive definition find the first 5 terms in the sequence

Answer 1

a₁, a₁ + 4, a₁ + 8, a₁ + 12, a₁ + 16, a₁ + 20

Answer 2

In the recursive formula, given above, d is the "common difference" between consecutive terms in the sequence.

So, if a₁ = 5 then here is the sequence:

a₂ = a_{(2 - 1)} +4 = a₁ + 4 = 5 + 4 = 9

a₃ = a_{(3 - 1)} +4 = a₂ + 4 = 9 + 4 = 13

a₄ = a_{(4 - 1)} +4 = a₃ + 4 = 13 + 4 =17

a₅ = a_{(5 - 1)} +4 = a₄ + 4 = 17 + 4 = 21

5, 9, 13, 17, 21, ...