172459210domain: NAppears in sequencesUnitary-sociable numbers (smallest member of each cycle).at n=12A000173Irregular triangle with 4 columns which contains in each row the members of a 4-cycle under the map x->A063919(x), iteration of summing the proper-unitary divisors.at n=8A098188Unitary sociable numbers of order 4.at n=8A319902