203693490domain: NAppears in sequencesa(1)=1; for n > 0, a(n+1) = rad(a(n))*n where rad=A007947.at n=21A066332Numbers with exactly 8 distinct prime divisors {2,3,5,7,11,13,17,19}.at n=20A147575Denominators of the probability of success in sultan's dowry problem with n daughters.at n=20A226243