Step variety: Difference between revisions
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=\displaystyle{\dfrac{r!}{n} \sum_{d\mid n} \phi(d) S(n/d, r)}</math> | =\displaystyle{\dfrac{r!}{n} \sum_{d\mid n} \phi(d) S(n/d, r)}</math> | ||
where <math>\phi</math> is the Euler totient function and <math>S(n, r)</math> is the Stirling number of the second kind | where <math>\phi</math> is the Euler totient function and <math>S(n, r)</math> is the Stirling number of the second kind which counts ways to partition an ''n'' element set into ''r'' distinguished parts. | ||
== List of named ternary scales == | == List of named ternary scales == | ||