What number comes next: 5, 11, 23, 47, ___?
Correct answer: D. 95
Each term is double the previous term plus 1: 5 × 2 + 1 = 11, 11 × 2 + 1 = 23, 23 × 2 + 1 = 47, so 47 × 2 + 1 = 95. When the terms roughly double each time, test a rule of the form "× 2 plus or minus a small number".
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