Question

Sequence 4,16,36,64,100

Answer 1

If you're looking for the rule, it's: they're all even squared numbers 
i.e. 2^2 = 4 , 4^4 = 16, etc.
if you're looking for more numbers, three more are: 12^12 = 144, 14^14 = 196, 16^16 =256

Answer 2

This is a quadratic sequence.
16-4=12 and 36-16=20
20-12=8
there is a common difference of 8, so you add 12 to the first term to get the second term, that means you will add 8+12=20 to the second term to get the third term, then you will add 8+20=28 to the third term to get the fourth term, and so on... it's called a common difference.
so
2nd term: 4+12=16
3rd term: 16+(8+12)=16+(20)=36
4th term: 36+(8+20)=36+(28)=64
5th term: 64+(8+28)=64+(36)=100