Question
3,   2,   3,  8,  31, Â
? What should come in place of the question mark (?) in the following number series?Solution
3 × 1 - 1 = 2 2 × 2 - 1= 3 3 × 3 - 1= 8 8 × 4 - 1 = 31 31 × 5 - 1= 154
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