In the following number series only one number is wrong. Find out the wrong number. 7, 7, 14, 28, 56, 224

The pattern is: multiply by 2, then multiply by 1, then multiply by 2, then multiply by 1... Starting with 7: 7×1=7, 7×2=14, 14×2=28 (should be 14×1=14), 28×2=56 (should be 14×2=28), 56×4=224 (should be 28×2=56). The number 56 breaks the pattern and should be 28. However, 56 is also part of the error cascade. The first actual error is at the fourth position where 28 should be 14, but 56 at position 5 is clearly wrong based on the alternating multiplication pattern.