# Super or subscript notation on the left hand side of a symbol?

Are there any commonly used notations with super or subscripts on the left hand side of the symbol? or on both sides of a symbol? If so, then what is the latex for having sup/sub script on left or both sides of a symbol.

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I often use a superscript on the left hand side to indicate the order of a tensor, e.g.

$$^4 \boldsymbol{C}$$

for the fourth-order stiffness tensor. Additionally, here in the Netherlands the base of a logarithm is often written as a superscript on the left hand side, e.g.

$$^2 \log 8 = 3$$

but I don't use this notation anymore as it tends to confuse people.

To conclude, a $\LaTeX$ related note: the superscript can be moved closer to the symbol by using \!, resulting in $^2 \! \log 8 = 3$.

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I do the same for pre-superscripts, but often put braces instead of leaving a blank: {}^3 G_1^2. \! is new and useful to me. –  Jeff Snider Jan 10 at 3:19

$_nC_r$ is sometimes used for $n\choose r$. I did this with _nC_r in dollar signs.

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Thanks, I forgotton about that, what about supersript on left or something with a sup/sub script on all sides, has anyone seen anything like that? –  Arjang Feb 26 '13 at 11:35
I have also seen $^nC_r$ used. –  Gerry Myerson Feb 26 '13 at 11:49
You can also attach superscripts and subscripts to an empty group {}. For example, {}_nC_r produces ${}_nC_r$. –  MJD Feb 26 '13 at 14:17

I've seen spectral sequences labelled as

$${}^{II} E^n_{p,q}$$

I've seen it suggested that one should use {}^a B to get ${}^aB$ rather than simply ^a B. There's probably something error prone about the latter, but I don't know what it is.

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In math mode, TeX (almost) just ignores spaces, so if you write x ^2 B you get $x ^2 B$, while x {}^2B gives $x {}^2B$. Here they recommend using the tensor package.

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Hypergeometric functions are written $_2 F _1$, which is _2F_1 in LaTeX.
Tetration—the operation that is iterated exponentiation much like exponentiation is iterated multiplication—is often notated with a superscript before the number. For example: $$4^{4^{4^4}}=^4\!\!4$$ The same thing could be shown using Knuth's up-arrow notation though: $$^44=4\uparrow\uparrow4$$ and I'm not sure how accepted the former notation is anymore.