What color codes can I use in my PS1 prompt?

function colorgrid( )

{

    iter=16

    while [ $iter -lt 52 ]

    do

        second=$[$iter+36]

        third=$[$second+36]

        four=$[$third+36]

        five=$[$four+36]

        six=$[$five+36]

        seven=$[$six+36]

        if [ $seven -gt 250 ];then seven=$[$seven-251]; fi



        echo -en "\033[38;5;$(echo $iter)m? "

        printf "%03d" $iter

        echo -en "   \033[38;5;$(echo $second)m? "

        printf "%03d" $second

        echo -en "   \033[38;5;$(echo $third)m? "

        printf "%03d" $third

        echo -en "   \033[38;5;$(echo $four)m? "

        printf "%03d" $four

        echo -en "   \033[38;5;$(echo $five)m? "

        printf "%03d" $five

        echo -en "   \033[38;5;$(echo $six)m? "

        printf "%03d" $six

        echo -en "   \033[38;5;$(echo $seven)m? "

        printf "%03d" $seven



        iter=$[$iter+1]

        printf '\r\n'

    done

}