As I said, it's a misnomer.

There is no formula with fixed N here because it operates with a 2^16 lookup table to avoid non-printable characters in both directions.

Edit

So the actual N(X) for a mapping

Y=R(X)

N(X)= N(Y)= Y-X

will vary near approximately 2^15-20+-8 (?).*

And it ignores anything >= 2^16 like emojis, similar to ROT13 ignoring any ASCII outside the alphabet.

Cheers Rolf
(addicted to the Perl Programming Language :)
Wikisyntax for the Monastery

*) Actually the description of the author was outdated and doesn't fit his code.

He's excluding 2100 characters.

In reply to Re^3: ROT8000 implementation? by LanX
in thread ROT8000 implementation? by jwkrahn

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