Find the odd man out from the series.
2, 6, 12, 20, 30, 44, 56, 72, 90, 110

Let's check the differences between successive terms of the series:
* $6-2=4$
* $12-6=6$
* $20-12=8$
* $30-20=10$
* $44-30=14$ (Discrepancy here)

The differences should form a continuous sequence of even numbers: $+4,+6,+8,+10,+12,+14,\dots$
If we add $12$ to $30$, we get $42$ instead of $44$.
Let's verify with $42$:

* $42+14=56$ (Matches next term)
* $56+16=72$
* $72+18=90$
* $90+20=110$

Thus, $44$ is the wrong number in the series.