Consider the number sequence: 3, 5, 9, 17, 33, ... What is the next number in this logic sequence?
65
Each number is formed by doubling the previous number and subtracting 1: (3*2)-1=5, (5*2)-1=9, (9*2)-1=17, (17*2)-1=33. Thus, (33*2)-1 = 65. (Alternatively, the difference doubles each time: +2, +4, +8, +16, +32).
About this riddle
Logic riddles give you a few facts and ask what must be true. List what you know, cross out what cannot be, and see what is left.
Difficulty: Easy. More like this: Logic riddles with answers or try Einstein's Logic Grid for a different kind of puzzle.
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