[Terr_]

192 bits?

I must be missing something here, there are 25 unique dice that can be permuted, each can have six potential sides showing, and 4 potential orientations of the displayed face... So (25!)×(25×6×4) ? Isn't that more like only 93 bits?

Well obviously harder to scan from a phone, I think a deck of playing cards would be easier to acquire and store. Shuffling 27 would give you 93 bits, shuffling the full 52 would be ~226.

[ecesena]

It’s explained in the link. I actually misremembered, it’s 196 bits.

[Terr_]

Never mind, with the benefit if sleep I see an error in my math.

Still, I wonder if a similar thing could be done by shuffling a deck of cards, and then riffling the results past a good camera so that an app can recognize the sequence in order. Perhaps it would be vulnerable to common shuffling mistakes?