Answer:
n^2+3
Step-by-step explanation:
Step 1:
Work out the first differences and that is 3, 5, 7, 9.
Step 2:
Find the second difference and that is 2.
Step 3:
Since half of 2 is 1, then the first term is n^2.
Step 4:
Subtracting n^2 from the sequence gives 3.
So the answer is n^2 + 3.
