k   = (inv(s) * ( z + r * pvk ) ) % N
s   = (inv(k) * ( z + r * pvk)  ) % N
pvk = (inv(r) *  ( (k*s)-z )    ) % N
r * pvk = (  (k*s)-z )  % N

r , s , z, private Key , k   
All may be odd or even numbers