What is the next number: 2, 3, 5, 9, 17, ?

Type:Math

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Hint: Each number is double the previous one, then minus one.

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The answer is

33

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2×2−1=3, 3×2−1=5, 5×2−1=9, 9×2−1=17, so 17×2−1=33.

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