add taglines to finite-field.{2,3,4}

posts/finite-field/2/index.qmd

@@ -1,7 +1,7 @@
 ---
 title: "Exploring Finite Fields, Part 2: Matrix Boogaloo"
 description: |
-  ...
+  How do we extend a field non-symbolically?
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posts/finite-field/3/index.qmd

@@ -1,7 +1,7 @@
 ---
 title: "Exploring Finite Fields, Part 3: Roll a d20"
 description: |
-  ...
+  When we extend fields with matrices, what other structures do we encounter?
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@@ -658,18 +658,18 @@ markdown $ ("$$" ++) $ (++ "$$") $ intercalate " \\quad " [
 
 We now have a correspondence between three elements of *A*~5~ and PSL(2, 5).
 We can "run" both sets of the generators until we associate all elements to one another.
-This is most visually appealing to see as a Cayley graph:
+This is most visually appealing to see as a Cayley graph[^3]:
 
 [
   ![
     Cayley graph showing an isomorphism between  A5 and PSL(2, 5). <br>
     Order-2 elements are red, order-3 elements are green, and order-5 elements are blue.
-    Purple arrows are order-5 generators, orange arrows are order-2 generators[^4].
+    Purple arrows are order-5 generators, orange arrows are order-2 generators.
   ](./a5_psl25_cayley.png){.narrow}
 ](./a5_psl24_cayley.png)
 
-[^4]: Different generators appear to be used for *A* and *B* in the above image
-      due to some self-imposed turbulence when writing the original post.
+[^3]: Different generators appear to be used for *A* and *B* due to some
+      self-imposed turbulence when writing the original post.
     Under projective equality, both are the same as our choices of *A* and *B*.
 
 

posts/finite-field/4/index.qmd

@@ -1,7 +1,7 @@
 ---
 title: "Exploring Finite Fields, Part 4: The Power of Forgetting"
 description: |
-  ...
+  Or: how I stopped learned to worrying and appreciate the Monad.
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