![enter image description here](https://i.stack.imgur.com/2OXZ4.png)

I want the '2' subscript to be proportionally smaller in the second alpha (the one in the fraction). As you can see, the alphas themselves are smaller, so their subscripts should be too. How should I accomplish this?

I am already using a newcommand in place of the default subscript command in order to make subscripts as small as possible:

```
\newcommand{\s}[2]{#1_{\scriptscriptstyle\rm #2}}

```