Question 132071
I don't see any pattern.  And I don't understand how you obtained 14.  One possible solution is 2, derived by the difference between 10 and 4 is 6.  Half of 6 is 3, which is the 3rd number.  Then the difference between 11 and 15 is 4.  Half of 4 is 2 which might be the next number.  I don't really see a series out of this, however.