$1 imes 2^3 + 1 imes 2^2 + 0 imes 2^1 + 1 imes 2^0 = 8 + 4 + 0 + 1 = 13$.
$1 imes 2^3 + 1 imes 2^2 + 0 imes 2^1 + 1 imes 2^0 = 8 + 4 + 0 + 1 = 13$।