Adding number to formula automatically


As I can see in LibreOffice Math guide (p29, the equations are numbered like this:
(#) [some equation] or (1) y=ax+b

How can I create an automatic formatting like this? My LO is v5. (Installed with the package manager, please don’t send me to compile the latest version).


Did you actually read the chapter “Formulas in Writer documents” starting on p29? The cryptic fn+F3 (two letters and the third function key) described there should be what you want. At least this works for me. It creates a table with two columns and one row where a default example of a formula (dummy / placeholder) is inserted into the left column and a number range field into the right column.
If you want to start the numbering anew for a new chapter e.g. you need to edit the ‘Number range’ field (dblclick) and replace the default ‘Value’ Text + 1 by the first numner you want to use.

===Editing 2020-10-19 about 20:20===
There was a related question with an enhanced answer here: How to typeset theorems and definitions?. The answer there is mainly about user-defined autotext entries for similar, but probably various purposes.

I’ve managed to remap fn+F3 to another keyboard shortcut. It does nothing.

I don’t understand.
-1- In a ‘Writer’ text create a new paragraph pressing ENTER.
-2- Hit three keys immediately consecutive: F, N and F3. Case of F and N shouldn’t matter.
-3- As by a wonder the one-row-two-column-table I told of will be created.
If this doesn’t work for you, tell your OS (exact version) and the version of your LibO to enable visitors of the thread to test.
I personally tested successfully with different versions of LibO including the recent under Win 10.

All I get is selected fn…

OS: Arch Linux

The fnF3 is an ‘AutoText’ > ‘Standard’ function. “fn” (or"FN") is the identifying code, and the special key F3 triggers the execution. “FN” must be separated from other text at least by spaces,cursor immediatly at the right. It would be strange but… Is your keyboard customized in a way undermining the F3 functionality?
Try > ‘Tools’ > ‘AutoText’ > ‘Standard’ > ‘Formula Numbering’.
Also look for the assignment to the F3 key in ‘Customize’, tab ‘Keyboard’. It should be ‘Run Autotext Entry’.

Well, that’s quite the mysterious trick! I had to read through all of the comments before I understood. But it worked well in my tests, Ubuntu Linux with LO and also Windows 10.

I think it’s important to note that using “fn” assumes that you have the English version of LibreOffice. In the French version, for example, you have to do nf+F3.

To hell with these silly “localizations”! They aren’t good for anything but undermine the ability of the community to help. Whoever is capable of keeping in mind a few dozen English terms should use an English UI and English function names in Calc. (I’m a German living in Germany.)
Here “fn” is meaningless anyway. It may remind of “function”. Shouldn’t it better remind of “typeset formula”? We can handle that, can’t we? I won’t file an enhancement request to change the letters to “tf”.

I read it. But when I press F3 (No fn on keyboard since there is no need for one) nothing happens.

you should type “f”, followed by “n”, and after that press F3.

The fn+F3 cryptic is a great tool in LibreOffice Writer. It creates a 1-row 2-column table spanning the text column, with a formula sample centered in the left column (Einstein mass-energy formula) with a large width, and the sequential number right justified in the right column, with a narrow width. This is great, but because of this structure, the equation is not centered on the page or text column. If a non-numbered formula is put before or after the numbered formula, one can clearly see that the equations are skewed. The solution would be to create a 1-row 3-column table, with the first and third columns narrow, with the same width, and the second one, containing the formula, center justified. This would make fn+F3 perfect.

I’ve searched for “LO cryptic fn+F3 equation not centered” with no success. Is there any way to edit the script for the cryptic, or can it be done by the LO Technical team?

This is not an answer and therefore you shouldn’t have used the Add Answer tool, but added a comment to a respective earlier post.
There is nothing cryptic. The special key F3 calls the autotext entry denoted by the few letters typed in advance.
Somebody using a formula editing tool will surely be clever enough to define an AutoText entry better meeting his (f/m) needs - if not satisfied with the predefined one.