What is the wrong digit in this sequence: 12,11,18,45,196,795,4734?

Answer 1

1. All the numbers except 11 are composite numbers (not prime).
   Another way 11 could be wrong is that the series could become ascending if it was replaced by any value >12 & 18<.
2. Only 196 is a perfect square.
3. 12 is the only outlier without which the series becomes ascending.