--- a/src/HOL/Probability/Probability_Mass_Function.thy Wed Aug 14 19:50:23 2019 +0200
+++ b/src/HOL/Probability/Probability_Mass_Function.thy Thu Aug 15 16:11:56 2019 +0100
@@ -856,7 +856,7 @@
have "integrable (map_pmf (to_nat_on M) M) (\<lambda>n. B)"
by auto
then show "summable (\<lambda>n. pmf (map_pmf (to_nat_on (set_pmf M)) M) n * B)"
- by (simp add: measure_pmf_eq_density integrable_density integrable_count_space_nat_iff summable_rabs_cancel)
+ by (fastforce simp add: measure_pmf_eq_density integrable_density integrable_count_space_nat_iff summable_mult2)
qed
qed simp
qed simp