Given the task definition and input, reply with output. The task is to generate the correct answer for a given math problem.

Problem: assume that f ( 1 ) = 0 and f ( m + n ) = f ( m ) + f ( n ) + 4 ( 9 mn - 1 ) . for all natural numbers ( integers > 0 ) m and n . what is the value of f ( 17 ) ?
4832