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.