src/HOL/Nat.thy
changeset 15341 254f6f00b60e
parent 15281 bd4611956c7b
child 15413 901d1bfedf09
equal deleted inserted replaced
15340:cd18d7b73a64 15341:254f6f00b60e
   562   apply (case_tac n)
   562   apply (case_tac n)
   563   apply (case_tac [2] nat)
   563   apply (case_tac [2] nat)
   564   apply (blast intro: less_trans)+
   564   apply (blast intro: less_trans)+
   565   done
   565   done
   566 
   566 
   567 subsection {* @{text LEAST} theorems for type @{typ nat} by specialization *}
   567 subsection {* @{text LEAST} theorems for type @{typ nat}*}
   568 
       
   569 lemmas LeastI = wellorder_LeastI
       
   570 lemmas Least_le = wellorder_Least_le
       
   571 lemmas not_less_Least = wellorder_not_less_Least
       
   572 
   568 
   573 lemma Least_Suc:
   569 lemma Least_Suc:
   574      "[| P n; ~ P 0 |] ==> (LEAST n. P n) = Suc (LEAST m. P(Suc m))"
   570      "[| P n; ~ P 0 |] ==> (LEAST n. P n) = Suc (LEAST m. P(Suc m))"
   575   apply (case_tac "n", auto)
   571   apply (case_tac "n", auto)
   576   apply (frule LeastI)
   572   apply (frule LeastI)