diff --git a/polycount/1/index.qmd b/polycount/1/index.qmd
index 3c65765..708d6c5 100644
--- a/polycount/1/index.qmd
+++ b/polycount/1/index.qmd
@@ -4,8 +4,8 @@ format:
   html:
     html-math-method: katex
 jupyter: python3
-date: "2021/02/03"
-date-modified: "2025/02/07"
+date: "2021-02-03"
+date-modified: "2025-02-07"
 categories:
   - algebra
   - phinary
diff --git a/polycount/2/index.qmd b/polycount/2/index.qmd
index cbc9fcf..f538211 100644
--- a/polycount/2/index.qmd
+++ b/polycount/2/index.qmd
@@ -3,8 +3,8 @@ title: "Polynomial Counting 2: Binary and beyond"
 format:
   html:
     html-math-method: katex
-date: "2021/02/05"
-date-modified: "2025/02/07"
+date: "2021-02-05"
+date-modified: "2025-02-07"
 categories:
   - algebra
   - binary
diff --git a/polycount/3/index.qmd b/polycount/3/index.qmd
index 8c01d96..8a9991b 100644
--- a/polycount/3/index.qmd
+++ b/polycount/3/index.qmd
@@ -4,7 +4,7 @@ format:
   html:
     html-math-method: katex
 date: "2021-02-06"
-date-modified: "2021-02-08"
+date-modified: "2025-02-08"
 jupyter: python3
 categories:
   - algebra
diff --git a/polycount/4/index.qmd b/polycount/4/index.qmd
index 88238cd..e4389cf 100644
--- a/polycount/4/index.qmd
+++ b/polycount/4/index.qmd
@@ -3,8 +3,8 @@ title: "Polynomial Counting 4: Two 2's"
 format:
   html:
     html-math-method: katex
-date: "2021-02-09"
-date-modified: "2/12/2025"
+date: "2021-02-06"
+date-modified: "2025-02-12"
 jupyter: python3
 categories:
   - algebra