20114953831domain: NAppears in sequencesIccanobirt numbers (12 of 15): a(n) = R(R(a(n-1)) + a(n-2) + a(n-3)), where R is the digit reversal function A004086.at n=31A102122Iccanobirt semiprimes (12 of 15): Semiprime numbers in A102122.at n=6A102202