21628080domain: NAppears in sequencesa(n) = ((7*n+10)(!^7))/10(1^7), related to A034830 (((7*n+3)(!^7))/3 sept-, or 7-factorials).at n=5A053106Numbers n such that there exists an x!=n that makes {x,x,x,n} an amicable multiset.at n=14A259305