Euler's number $e=2.71828 18284 59045... $ can be approximated by the rational number: $$ x=\frac{271,828-27}{100,000-10}= \frac{271,801}{99,990} =2.7182818281... $$
Also, $e$ has the well-known continued fraction expansion $$ e = [2;1,2,1,1,4,1,1,6,1,1,8,1,1,10,1,1,12,...]. $$
Is the fraction $x$ a semiconvergent of $e$? That is, does there exist $ a $ such that
$$
x=\frac{h_{n-1} +a h_n}{k_{n-1}+a k_n},
$$
where $h_{n-1}, h_n$ and $k_{n-1}, k_n$ are successive numerators and denominators of convergents of $e$.
Background
It is known that $y=355/113$ is a close rational approximation to $\pi$ which is also easy to remember (113 355). I want to know if there is a similar way to relate $2.718281828...$ to $e$.
Yes!
In Mathematica, define
Then
Gives