1968515515domain: NAppears in sequencesIccanobirt numbers (10 of 15): a(n) = R(a(n-1) + R(a(n-2)) + a(n-3)), where R is the digit reversal function A004086.at n=31A102120Iccanobirt semiprimes (10 of 15): Semiprime numbers in A102120.at n=5A102200