$2^{1} = 2$;
$2^{2} = 4$;
$2^{3} = 8$;
$2^{4} = 16$;
$2^{5} = 32$;
$2^{6} = 64$;
$2^{7} = 128$;
$2^{8} = 256$;
$2^{9} = 512$;
$2^{10} = 1024$.