missing dollar sign

Author: prisae

docs/paper.md

@@ -68,7 +68,7 @@ ESMDA coefficient (or inflation factor) is denoted by $\alpha$, and the
 predicted and perturbed data vectors by $d^f$ and $d_{\text{uc}}$,
 respectively. The equation is evaluated for $i$ data assimilation steps, where
 $i$ is typically a low number between 4-10. The $\alpha$ can change in each
-step, as long as $\sum_i \frac{1}{\alpha_i} = 1. Common are either constant
+step, as long as $\sum_i \frac{1}{\alpha_i} = 1$. Common are either constant
 values or series of decreasing values. The algorithm's implementation in
 `dageo` includes optimizations for computational efficiency and numerical
 stability.