KöMaL 2018 C1461

The operation $\circ$ is defined on positive integers. Given that $i)$ $1 \circ 1=3$; $ii)$ $a\circ b=b\circ a$ for all $a$, $b$; $iii)$ $a \circ (b+1) = a\circ b + (a+1) + 2b$ for all $a$, $b$, determine the value of $2017\circ 2018$.