0
The alternating factorial is defined as
$$
\large\operatorname{af}(n) = \sum_{i=1}^n(-1)^{n-i}i!
$$
where \$i!\$ is the regular factorial of \$i\$:
$$
\large i!=
\begin{cases}
1, & \text{if $\;i=0$} \\
i\times(i-1)\times(i-2)\times\dots\times2\times1, & \text{otherwise}
\end{cases}
$$
For example...
Identify 22edo intervals
Objective
Given the distance between two keys in an octave, identify its name.
But there's a caveat. In this challenge, there are 22 keys in an octave, not usual 12.
Here, porcupine[7] scale will be assumed.
Mapping
White keys are marked bold.
Distance
Name
0
Unis...
