author | wenzelm |
Fri Mar 01 16:59:48 2002 +0100 (2002-03-01) | |
changeset 12997 | 80dec7322a8c |
parent 12996 | 7ac0a7e306db |
child 12998 | 03b9afa801df |
1.1 --- a/src/HOL/Isar_examples/Puzzle.thy Fri Mar 01 16:24:43 2002 +0100 1.2 +++ b/src/HOL/Isar_examples/Puzzle.thy Fri Mar 01 16:59:48 2002 +0100 1.3 @@ -24,8 +24,7 @@ 1.4 show ge: "!!n. n <= f n" 1.5 proof - 1.6 fix k show "!!n. k == f n ==> n <= k" (is "PROP ?P k") 1.7 - proof (induct k 1.8 - rule: nat_less_induct [rule_format]) 1.9 + proof (induct k rule: less_induct) 1.10 fix k assume hyp: "!!m. m < k ==> PROP ?P m" 1.11 fix n assume k_def: "k == f n" 1.12 show "n <= k"