fact: Definition negligible (mu : set T -> \bar R) N := exists A, [/\ measurable A, mu A = 0 & N `<=` A].
imports: mathcomp(all_ssreflect all_algebra finmap) mathcomp(mathcomp_extra boolp classical_sets functions) mathcomp(cardinality fsbigop ) reals ereal signed topology normedtype sequences esum numfun HB(structures)