One term in the number series is wrong. Find out the wrong term.
1, 3, 10, 21, 64, 129, 356, 777

Explanation:-

The correct pattern is x 2 + 1, x 3 + 1, x 2 + 1, x 3 + 1,.....
So, 356 is wrong and must be replaced by (129 x 3 + 1) i.e. 388.