12.
The next number in the series will be 66. The next number is found by adding the two previous numbers. (2+7=9, 9+7=16, etc...)
33
7
17?
From the given sequence, the pattern appears to be 47-42=4, 42/3=14, 14*2=28, 28-4=24, 24/3=8, 8*2=16 and therefore the next number will be 16-4=12.
256 is the next number, 3+5=8. 3+5+8=16. 3+5+8+16=32. and so on.
The next square number after 16 is 25
11 15 16
5
15
15
35