查看原题'" class='mdui-btn mdui-btn-raised'>点击加载点击跳转$$\sum{i=1}^A\sum{j=1}^B [\gcd(i,j)=d]\=\sum{i=1}^{\left \lfloor \frac Ad \right \rfloor}\sum{j=1}^{\left \lfloor \frac Bd\right \rfloor} [\gcd(i,j)=1]\=\sum{i=1}^{\left \lfloor \frac Ad \right \rfloor}\sum{j=1}^{\left \lfloor \frac Bd\right \rfloor} \……