#!/bin/bash

#https://askubuntu.com/questions/27314/script-to-display-all-terminal-colors

for x in {0..8}; do 
    for i in {30..37}; do 
        for a in {40..47}; do 
            echo -ne "\e[$x;$i;$a""m\\\e[$x;$i;$a""m\e[0;37;40m "
        done
        echo
    done
done

echo ""

# oneliner : for x in {0..8}; do for i in {30..37}; do for a in {40..47}; do echo -ne "\e[$x;$i;$a""m\\\e[$x;$i;$a""m\e[0;37;40m "; done; echo; done; done; echo ""