2n² + n + 1
<u>Explanation:</u>
The sequence is 4, 11, 22, 37
Difference between: 7, 11, 15
The first differences are 7, 11, 15, and the second differences are 4.
Since half of 4 is 2, then the first term will be 2n^2.
Subtracting 2n² from the sequence gives 2, 3, 4, 5 which has nth term n + 1.
Therefore the final answer is 2n² + n + 1
