<h1>Mixed series-Find the missing number</h1>

 

Find the missing number and complete series

It's not so easy to solve it.

This is a mixed series

Below you can see the solution and the pattern

5=4x1+1

12=5x2+2

39=12x3+3

160=39x4+4

So 

160x5+5=805

Correct answer is 805