You can put this solution on YOUR website! Most of these type problems are practice. I like to start by looking at the series of numbers. You can see the difference in the inputs goes up by 1 one each entry. Now look and see if you can find a pattern in the output numbers.
You can see they are getting larger by increasingly larger amounts. However, nothing obvious jumps out a bout their values. So, the first thing I like to try is to see if there are patterns in the series of outputs. For instance, perhaps every other number has an obvious pattern. One thing I always try is finding the difference between each successive output number.
difference between 5 and 3 = 2
difference between 9 and 5 = 4
difference between 17 and 9 = 8 do you see the pattern yet
difference between 33 and 17 = 16
So each output increases by a value that is power of 2. Now all that is left to figure out is what the 'starting' value is. A little trail and error will show you that value is 1.
So, the function that fits the given data points is x>=1
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