changeset 6944 | 214e41d27d74 |
parent 6854 | 60a5ee0ca81d |
child 7133 | 64c9f2364dae |
--- a/src/HOL/Isar_examples/NatSum.thy Fri Jul 09 10:49:14 1999 +0200 +++ b/src/HOL/Isar_examples/NatSum.thy Fri Jul 09 16:44:55 1999 +0200 @@ -33,13 +33,13 @@ qed "sum_of_naturals"; *) -theorem "2 * sum (%i. i) (Suc n) = n * Suc n"; +theorem sum_of_naturals: "2 * sum (%i. i) (Suc n) = n * Suc n"; proof same; apply simp_tac; apply (induct n); apply simp_tac; apply asm_simp_tac; -qed_with sum_of_naturals; +qed; text {* Proper Isabelle/Isar proof expressing the same reasoning (which