[Tex/LaTex] ny repository of latex equations for standard equations in maths, physics, etc.

repositories

We all have to write and rewrite the equations that have been known for thousands of years. Is there any repository where, say, the Pythagorean's theorem can be fetched as $a^2 + b^2 = c^2$?

Update: By 'repository' I mean a browsable/downloadable database, where if you type "Pythagorean theorem", you get the string $a^2 + b^2 = c^2$ (or the several well-known ways of representing it).

Note: Springer's database is clearly not that kind of repository.

Best Answer

Yes, there is! In some sense, at least for mathematics.

The NIST Digital Library of Mathematical Functions allows you to download for each equation its LaTeX representation. Click on the information symbol on the right of any equation and then click on the "TeX encoding": it will download the LaTeX form.

For instance, for the equation 5.10.1, it reports

\[\mathop{\mathrm{Ln}\/}\nolimits\mathop{\Gamma\/}\nolimits\!\left(z\right)+z-%
\left(z-\tfrac{1}{2}\right)\mathop{\ln\/}\nolimits z-\tfrac{1}{2}\mathop{\ln\/%
}\nolimits\!\left(2\pi\right)=\cfrac{a_{0}}{z+\cfrac{a_{1}}{z+\cfrac{a_{2}}{z+%
\cfrac{a_{3}}{z+\cfrac{a_{4}}{z+\cfrac{a_{5}}{z+}}}}}}\cdots,\]