https://s0.wp.com/latex.php?latex=%5Cdisplaystyle%7B+D%28p%29+%3D+%5Cfrac%7B1%7D%7B2%7D%5Csum_%7Bi%2Cj%7D+H_%7Bij%7Dq_j+%5Cleft%28+%5Cfrac%7Bp_j%7D%7Bq_j%7D+-+%5Cfrac%7Bp_i%7D%7Bq_i%7D+%5Cright%29%5E2+%7D+&bg=ffffff&fg=333333&s=0&c=20201002