The search in SE 2.0 is indeed better and slightly more sophisticated, but it still lacks a lot of options; not to mention that the LaTeX support is still abysmal and nonexistent.
]]>There are a few issues with this kind of search. Briefly:
G_2, G_{2}, \newcommand{\Gee}[1]{\ensuremath{G_{#1}}}\Gee2, etc.)Our tips page has some useful info for searching MO.
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