When I apply the Mathematica command TeXForm to
DifferenceRoot[
Function[{\[FormalY], \[FormalN]}, {9 (1 + \[FormalN])^2 \
\[FormalY][\[FormalN]] -
60 (3 + 2 \[FormalN])^2 \[FormalY][
1 + \[FormalN]] + (3840 + 4096 \[FormalN] +
1024 \[FormalN]^2) \[FormalY][2 + \[FormalN]] ==
0, \[FormalY][1] == -(9/64), \[FormalY][2] == -(81/4096)}]][bb]
I obtained
\text{DifferenceRoot}\left[\{\unicode{f818},\unicode{f80d}\}\unicode{f4a1}\left\{\left(10
24 \unicode{f80d}^2+4096 \unicode{f80d}+3840\right) \unicode{f818}(\unicode{f80d}+2)+9
(\unicode{f80d}+1)^2 \unicode{f818}(\unicode{f80d})-60 (2 \unicode{f80d}+3)^2
\unicode{f818}(\unicode{f80d}+1)=0,\unicode{f818}(1)=-\frac{9}{64},\unicode{f818}(2)=-
\frac{81}{4096}\right\}\right][\text{bb}]
which was not accepted as the input to \begin{equation} \end{equation} in my question https://mathoverflow.net/questions/322958/compute-the-two-fold-partial-integral-where-the-three-fold-full-integral-is-kno/323011#323011
because the "Argument to unicode must be a number".
I had posed this question first on the TeXstackexchange https://tex.stackexchange.com/posts/474568/edit and was redirected here, although a number of technical responses was given.
U+f818etc..) are in a en.wikipedia.org/wiki/Private_Use_Areas, which means that their interpretation is application-specific and may mean different things to different applications. $\endgroup$\unicodeis not defined by default and I was unable to find any package that would define it in such a way that Mathematica's output would get compiled. $\endgroup$TeXFormis long overdue for an update and it should be able to produce more reasonable TeX code for many of these characters. Not even the newAssociationdelimiters are supported, introduced in version 10.0 I think TeXForm stopped getting updates way before then ... $\endgroup$