# How to type three points diagonally?

In an equation, I want to display three points like "...", but instead of horizontally, they should be diagonally. I'm sure there must be a command to do that, but a google search did not really help.

Any idea?

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"\ddots"; see also detexify.kirelabs.org/classify.html –  Grigory M Aug 9 '10 at 8:31
You should out that into an answer (so that it can be accepted). –  Caramdir Aug 9 '10 at 8:33
That's what I was looking for Grigory M. Thank you. Put it in an answer so I can accept it... –  Nigu Aug 9 '10 at 8:41
I looked in the tables.pdf file provided with texshop, but didn't find this specific command. I'll have a look at your other references... –  Nigu Aug 9 '10 at 8:42
@Grigory: We have had lots of questions for symbols which were easily resolved by detexify or symbols. I think it is better to answer them and add a link to detexify, symbols or the general questions, than to close them. However, you can open a question on meta to discuss this. –  Caramdir Aug 9 '10 at 8:44
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The command is called \ddots. See also http://tex.stackexchange.com/questions/14/how-to-look-up-a-math-symbol (esp. detexify).

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Indeed, detexify does the trick! Thanks –  Nigu Aug 9 '10 at 8:49

The mathdots package (besides fixing up the behaviour of (La)TeX \ddots and \vdots when the font size changes) provides an “inverse diagonal” ellipsis \iddots

That is, \iddots is three dots sloping forwards while \ddots is three dots sloping backwards.

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An alternative to the \iddots (inverse diagonal dots) from the mathdots package:

\makeatletter
\def\Ddots{\mathinner{\mkern1mu\raise\p@
\vbox{\kern7\p@\hbox{.}}\mkern2mu
\raise4\p@\hbox{.}\mkern2mu\raise7\p@\hbox{.}\mkern1mu}}
\makeatother


Then call with \Ddots

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