See suggestion: https://forums.factorio.com/viewtopic.php?f=33&t=73454
See also:
https://wiki.factorio.com/Tutorial:Circuit_network_cookbook#Multicolor_Display_by_DaveMcW
https://forums.factorio.com/download/file.php?id=51756
LED arithmetic combinator with LED lamp and arithmitic combinator
Mods introducing new content into the game.
See suggestion: https://forums.factorio.com/viewtopic.php?f=33&t=73454
See also:
https://wiki.factorio.com/Tutorial:Circuit_network_cookbook#Multicolor_Display_by_DaveMcW
https://forums.factorio.com/download/file.php?id=51756