write python code with absolutely no strings please.

A number is an ein number $($short for even increasing number$)$ if the even digits in the number are strictly increasing from left to right. The odd digits in the number can be in any order.

For example, $2478$ is an ein number because the even digits $248$ are in increasing order. However, $14236$ is not an ein number, since the even digits $426$ are not in increasing order. Note that $137$ is also an ein number because there are no even digits, so we will say that the even digits are implicitly in order. Also note that $22$ is not an ein number because repeating even digits are not increasing.

With this in mind, write the function nthEinNumber$($n$)$ which takes a non$-$negative int n and returns the nth ein number.