I need the equation for these numbers:

Question

3, 9, 19, 33, 51

I see that the pattern goes up by 6, then 10, then 14, then 18 (4 more each time)

Answer 1

I tried this:
subtract 1 from each .... 2,8,18,32,50
divide each by 2 .... 1,4,9,16,25...
do you recognize these numbers?

mmmh!
now pick a number n, and perform the above steps with their "inverse" operation in reverse order.

Answer 2

thanks

Answer 3

Did you get
number = 2n^2 + 1