src/HOL/Power.ML
changeset 8861 8341f24e09b5
parent 8442 96023903c2df
child 8935 548901d05a0e
equal deleted inserted replaced
8860:6bbb93189de6 8861:8341f24e09b5
    21 
    21 
    22 Goal "0 < i ==> 0 < i^n";
    22 Goal "0 < i ==> 0 < i^n";
    23 by (induct_tac "n" 1);
    23 by (induct_tac "n" 1);
    24 by (ALLGOALS (asm_simp_tac (simpset() addsimps [zero_less_mult_iff])));
    24 by (ALLGOALS (asm_simp_tac (simpset() addsimps [zero_less_mult_iff])));
    25 qed "zero_less_power";
    25 qed "zero_less_power";
       
    26 Addsimps [zero_less_power];
       
    27 
       
    28 Goal "!!i::nat. 1 <= i ==> 1 <= i^n";
       
    29 by (induct_tac "n" 1);
       
    30 by Auto_tac;
       
    31 qed "one_le_power";
       
    32 Addsimps [one_le_power];
    26 
    33 
    27 Goalw [dvd_def] "!!(m::nat) (i::nat). m<=n ==> i^m dvd i^n";
    34 Goalw [dvd_def] "!!(m::nat) (i::nat). m<=n ==> i^m dvd i^n";
    28 by (etac (not_less_iff_le RS iffD2 RS add_diff_inverse RS subst) 1);
    35 by (etac (not_less_iff_le RS iffD2 RS add_diff_inverse RS subst) 1);
    29 by (asm_simp_tac (simpset() addsimps [power_add]) 1);
    36 by (asm_simp_tac (simpset() addsimps [power_add]) 1);
    30 by (Blast_tac 1);
    37 by (Blast_tac 1);