It is: 34
A single number, such as 4642142824816 does not constitute a sequence.
My guess: 2.5
16
This is a sequence of perfect squares. 12=1, 22=4, 32=9, 42=16, 52=25. The next number is 62=36.
17?
16 is the next squared number.
The next number in the sequence 2, 4, 16, 64 is 256.
a
It would be 16. The sequence is doubling pairs. 3 and 4 go on to be 6 and 8. 6 and 8 would go on to be 12 and 16. 12 and 16 would go on to be 24 and 32, and so on.
The next number in the sequence is... 64
92 - 18 = 72 72 - 16 = 56 56 - 14 = 42 42 - 12 = 30 30 - 10 = 20 20 is the next number in the sequence.
The next number in this sequence should be 33.