As you would have noticed the pattern.
The pattern goes like :
1 to 4 = gap of 3
4 to 9 = gap of 5
9 to 16 = gap of 7
16 to 25 = gap of 9
You can observe the gap is increasing by 2 as the sequence progresses.
So the next term would be at the gap of 11 and the term would be 36.
There is another solution to this question :
1² = 1
2² = 4
3² = 9
4² = 16
5² = 25
So, next will be 6’s square = 36
So, second term is 7² = 49
Solve with any pattern, the answer will be 36.