Description: The cardinality of a disjoint union, not necessarily finite. cf. hashuni . (Contributed by Thierry Arnoux, 19-Nov-2016) (Revised by Thierry Arnoux, 2-Jan-2017) (Revised by Thierry Arnoux, 20-Jun-2017)
Ref | Expression | ||
---|---|---|---|
Assertion | hasheuni | |