3^2013=3*3^2012=3*9^1006=3*(8+1)^1006=3*(M8+1)=3*M8+3;
5^2013=5*5^2012=5*25^1006=5*(M8+1)^1006=5*(M8+1)=5*M8+5;
3^2013+5^2013=M8+8;
4^2013 se divide prin 8 ⇒ 3^2013+4^2013+5^2013 se divide prin 8;
4^2013=4*4^2012=4*16^1006=4*(9+7)^1006=4*(M9+7);
5^2013=5*5^2012=5*25^1006=5*(18+7)^1006=5*(M9+7);
4^2013+5^2013=9M9+28+35=M9+63=M9;
3^2013 se divide prin 9 ⇒ 3^2013+4^2013+5^2013 se divide prin 9;
am demonstrat ca numarul se divide prin 8 si prin 9 si, deoarece, 8 si 9 sunt prime intre ele, numarul se divide prin [8,9]=72.