Find the wrong number in the given series 4 9 19 40 79 159

The intended pattern for this series is to multiply the previous number by 2 and then alternately add 1 or subtract 1. The generated sequence should be 4, (4 x 2) + 1 = 9, (9 x 2) - 1 = 17, (17 x 2) + 1 = 35, and (35 x 2) - 1 = 69. Since the given number 40 breaks this logical progression, it is the incorrect term. The result is 40.

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