[latexrefman] \bigtriangleup appears to be a binary operator

[Karl Berry]

    Does this mean that \bigtriangleup is actually a binary operator?
    The same applies to \bigtriangledown as well.

Evidently yes, since the LaTeX source declares them with \mathbin:

fontdef.dtx:1007:\DeclareMathSymbol{\bigtriangleup}{\mathbin}{symbols}{"34}
fontdef.dtx:1008:\DeclareMathSymbol{\bigtriangledown}{\mathbin}{symbols}{"35}

By the way, I see there is also:
fontdef.dtx:1015:\DeclareMathSymbol{\varbigtriangleup}{\mathbin}{symbols}{"34}
fontdef.dtx:1016:\DeclareMathSymbol{\varbigtriangledown}{\mathbin}{symbols}{"35}

though I'm not sure what fonts actually have a "var" form for these.

Probably there are other discrepancies between our table and the reality. 
Maybe one day someone will do a systematic check. Meanwhile, I'll at
least fix these two.

Thanks for the report. --best, karl.