equal
deleted
inserted
replaced
702 proof |
702 proof |
703 fix x |
703 fix x |
704 have "P x \<longrightarrow> P (x - i * d)" using step.hyps by blast |
704 have "P x \<longrightarrow> P (x - i * d)" using step.hyps by blast |
705 also have "\<dots> \<longrightarrow> P(x - (i + 1) * d)" |
705 also have "\<dots> \<longrightarrow> P(x - (i + 1) * d)" |
706 using minus[THEN spec, of "x - i * d"] |
706 using minus[THEN spec, of "x - i * d"] |
707 by (simp add:int_distrib Ring_and_Field.diff_diff_eq[symmetric]) |
707 by (simp add:int_distrib OrderedGroup.diff_diff_eq[symmetric]) |
708 ultimately show "P x \<longrightarrow> P(x - (i + 1) * d)" by blast |
708 ultimately show "P x \<longrightarrow> P(x - (i + 1) * d)" by blast |
709 qed |
709 qed |
710 qed |
710 qed |
711 |
711 |
712 lemma incr_mult_lemma: |
712 lemma incr_mult_lemma: |