\(Ư\left(15\right)=\left\{\pm1;\pm3;\pm5;\pm15\right\}\)
\(B\left(15\right)=\left\{0;\pm15;\pm30;\pm45;\pm60;...\right\}\)
\(Ư\left(50\right)=\left\{\pm1;\pm2;\pm5;\pm10;\pm25\right\}\)
\(B\left(50\right)=\left\{0;\pm50;\pm100;...\right\}\)
\(Ư\left(80\right)=\left\{\pm1;\pm2;\pm4;\pm5;\pm8;\pm10;\pm20;\pm40\right\}\)\(B\left(80\right)=\left\{0;\pm80;\pm160;...\right\}\)