diff --git a/gcs/doc.go b/gcs/doc.go
index 2056b4d..780fd76 100644
--- a/gcs/doc.go
+++ b/gcs/doc.go
@@ -10,7 +10,7 @@ Golomb-Coded Set
 
 A Golomb-coded set is a probabilistic data structure used similarly to a Bloom
 filter. A filter uses constant-size overhead plus on average n+2 bits per
-item added to the filter, where 2^-1 is the desired false positive (collision)
+item added to the filter, where 2^-n is the desired false positive (collision)
 probability.
 
 GCS use in Bitcoin