Answer:
2, 5, 9, 19
Step-by-step explanation:
Using the recursive formula f(n) = 2f(n - 2) + f(n - 1)
with f(1) = 2 and f(2) = 5
f(3) = 2f(3 - 2) + f(3 - 1)
= 2f(1) + f(2) = (2 × 2) + 5 = 4 + 5 = 9
f(4) = 2f(4 - 2) + f(4 - 1)
= 2f(2) + f(3) = (2 × 5) + 9 = 10 + 9 = 19
