src/HOL/Algebra/Ideal.thy
changeset 35849 b5522b51cb1e
parent 35848 5443079512ea
child 41433 1b8ff770f02c
--- a/src/HOL/Algebra/Ideal.thy	Sun Mar 21 16:51:37 2010 +0100
+++ b/src/HOL/Algebra/Ideal.thy	Sun Mar 21 17:12:31 2010 +0100
@@ -1,6 +1,5 @@
-(*
-  Title:     HOL/Algebra/CIdeal.thy
-  Author:    Stephan Hohe, TU Muenchen
+(*  Title:      HOL/Algebra/CIdeal.thy
+    Author:     Stephan Hohe, TU Muenchen
 *)
 
 theory Ideal
@@ -45,6 +44,7 @@
   done
 qed
 
+
 subsubsection (in ring) {* Ideals Generated by a Subset of @{term "carrier R"} *}
 
 definition
@@ -71,6 +71,7 @@
   show ?thesis  by (intro principalideal.intro principalideal_axioms.intro) (rule is_ideal, rule generate)
 qed
 
+
 subsubsection {* Maximal Ideals *}
 
 locale maximalideal = ideal +
@@ -93,6 +94,7 @@
     (rule is_ideal, rule I_notcarr, rule I_maximal)
 qed
 
+
 subsubsection {* Prime Ideals *}
 
 locale primeideal = ideal + cring +
@@ -139,6 +141,7 @@
     done
 qed
 
+
 subsection {* Special Ideals *}
 
 lemma (in ring) zeroideal:
@@ -867,6 +870,7 @@
   qed
 qed
 
+
 subsection {* Derived Theorems *}
 
 --"A non-zero cring that has only the two trivial ideals is a field"