[Tex/LaTex] How to make an old school “much less/greater” (<< and >>) symbol

math-modesymbols

How can the old school "much less (or greater)" – << and >> – symbol:

enter image description here

be made? I haven't succeeded with http://detexify.kirelabs.org.

Note I don't want the common \ll & \gg symbols.

Best Answer

The mathabx package provides this glyph as \lll (and correspondingly \ggg). However, mathabx changes a lot of symbols. If you want only these two you may easily adapt the code from Importing a Single Symbol From a Different Font

\documentclass{article}

\DeclareFontFamily{U}{matha}{\hyphenchar\font45}
\DeclareFontShape{U}{matha}{m}{n}{
      <5> <6> <7> <8> <9> <10> gen * matha
      <10.95> matha10 <12> <14.4> <17.28> <20.74> <24.88> matha12
      }{}
\DeclareSymbolFont{matha}{U}{matha}{m}{n}

\DeclareMathSymbol{\Lt}{3}{matha}{"CE}
\DeclareMathSymbol{\Gt}{3}{matha}{"CF}

\begin{document}

$a \ll b \Lt c \Gt d \gg e$

\end{document}

enter image description here

EDIT I was reminded in comments that \lll and \ggg are defined also in amssymb (and other math font packages) to do something else. The names \Lt, \Gt (from stix. unicode-math & others) avoid such clashes.

The nice answer by Davislor also shows how to import these symbols from the stix fonts, though in that case I'd switch fonts completely. In a Computer Modern setting I find the mathabx symbols more suitable.