.bash_profile for iTerm2 tabs colored by tty

iterm-bash_profile.sh

if [ "iTerm.app" == "$TERM_PROGRAM" ] ; then 
        # set up an array of RGB values
        tabcolors[0]="244,0,200"
        tabcolors[1]="0,200,244"
        tabcolors[2]="68,250,132"
        tabcolors[3]="250,68,132"
        tabcolors[4]="250,132,68"
        tabcolors[5]="220,200,100"

        TTYNUM=`ps -p $$ -o tty= | cut -c 5,6,7`

        # get the color at index ($TTY MOD $ARRAY_LENGTH)
        tci=`expr $TTYNUM % ${#tabcolors[*]}`
        TABCOLOR="${tabcolors[$tci]}"

        # split the r,g,b values into RGB array
        OIFS=$IFS
        set -- "$TABCOLOR"
        IFS=","; declare -a RGB=($*)
        IFS=$OIFS

        # output proprietary ansi codes for the iterm tab color 
        echo -e "\033]6;1;bg;red;brightness;${RGB[0]}\a\c"
        echo -e "\033]6;1;bg;green;brightness;${RGB[1]}\a\c"
        echo -e "\033]6;1;bg;blue;brightness;${RGB[2]}\a\c"
fi