Algorithm that matches decimal number to expression in terms of mathematical constants

Question

I remember finding at some point a type of algorithm which provided a decimal value with enough precision, would try to match it to expressions in terms of mathematical constants (for example, plugging in $5.85987448204$ would return $\pi+e$.)

But I cant't seem to find anything like this on the internet, so does anybody have any idea about how these algorithms are called, or where I could find something like this?

Answer 1

See Simon Plouffe's Inverse Symbolic Calculator and Robert Munafo's RIES - Find Algebraic Equations, Given Their Solution.

Answer 2

You might explore Ries, specifically about the Ries algorithm.