```
\begin{align*}
\begin{array}{c}
\min \: A = \min \: \sum_{i\in B} C_i
\\ \\
\min \: D = \min \: \sum_{i\in B} \pi_i \cdot F_i
\end{array}
\end{align*}
```

How can I get `i \in B`

below the `\sum`

symbol without breaking the `align`

into multiple aligns?

## Best Answer

By putting a

`\displaystyle`

in front of the`\sum`

. You basically want the font to behave like it does in a top-level environment, because it's nested in an array it gets assigned a`\textstyle`

font size.Why you're not aligning the equations on the equals sign beats me though. It might be better to use two

`equation`

environments in this case, the code wouldn't look so bloated as it does now.