Øistein E. Andersen:
Currently, only a limited set of vulgar fractions can be expressed
in HTML, viz, those that exist as pre-composed characters in
Unicode. (...)
1) According to Unicode (...), `any sequence of one or more decimal
digits, followed by the fraction slash [U+2044], followed by any
sequence of one or more decimal digits ... should be displayed as a
unit, such as ¾'.
FWIW, JFTR and FYI, Wikipedia has a 'frac' template <http://
en.wikipedia.org/wiki/Template:Frac> whose code has changed over
time, but always used the fraction slash, and may be different in
other Wikipedias (or Mediawikis).
