Write the first four terms of the arithmetic sequence with a_{1} = 4 and d = 5.

To get from one term to the next we add d = 5. So

a_{2} = a_{1} + 5 = 9

a_{3} = a_{2} + 5 = 14

a_{4} = a_{3} + 5 = 19

We were given the first term, a_{1} = 4. The first four terms are

4, 9, 14, 19.