diff --git a/README.md b/README.md
index 081cadc..f7e0380 100644
--- a/README.md
+++ b/README.md
@@ -5,5 +5,5 @@ This utility (age-gen-passphrase) generates secret and public keys (into stdout)
 Strong password highly recomended
 
 ## Password selection
-To keep entropy at at the same level of $\geq 2^256$ bits, you should use long password.
-Exact amount of required characters can be calculated by formula: $\ceil*{256 / log_2(Nchars)}$
+To keep entropy at at the same level of $\geq 2^{256}$ bits, you should use long password.
+Exact amount of required characters can be calculated by formula: $\lceil 256 / log_2(Nchars) \rceil$