This is TeX, Version 3.14159 (Web2C 7.3.7) (format=tex 2002.8.9)  23 NOV 2002 18:34
**$$\root 3 \of x+1$$
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                   \mathchoice 
\mathpalette #1#2->\mathchoice 
                               {#1\displaystyle {#2}}{#1\textstyle {#2}}{#1\...
<*> $$\root 3 \of x
                   +1$$
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<*> $$\root 3 \of x+1$$
                       
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