It is possible to see something close (how close I don't know) by saturating the S & M cones instead of avoiding them. Wikipedia refers to these as 'chimerical colors':
I've always taken it to be that the color is unique to the situation/viewer -- a sort of pearlescent void-color that can't be described in any known language, but which just Is. More a physical phenomenon than an actual color, but distinctly hued somehow.
Having read this comment from today detailing variance in the default Windows 95 background (https://news.ycombinator.com/item?id=49329282), I'm imagining Olo would be your wallpaper if "257 colors" could be supported.
The word "officially" is the massive wiggle-word here.
Only one person on Earth has officially seen the color of my coffee mug. Send me Venmo for $10, and I'll officiate your viewing of the attached JPG....
Except that this requires extremely specialized equipment to individually trigger specific cone cells in your eyes, so I expect they have a pretty damn good idea of who has seen this and who hasn't.
https://en.wikipedia.org/wiki/Impossible_color#Chimerical_co...
https://www.skytopia.com/project/illusion/ipage-et.html
https://youtu.be/wh4aWZRtTwU
https://en.wiktionary.org/wiki/octarine
Note that those are possibly photosensitive epilepsy risks if you turn them up to 60/100.
I suspect many animals experience color quite differently, including seeing infrared/ultraviolet, etc.
Basically equivalent to
source: trust me bro
Only one person on Earth has officially seen the color of my coffee mug. Send me Venmo for $10, and I'll officiate your viewing of the attached JPG....
I was trying to find the color between red and violet, then I discovered that exact opposite is very weird.
Try 0xFF0030 and invert it.
The color in the Wikipedia article is just a rough approximation.