109838domain: NAppears in sequencesBecomes prime after exactly 9 iterations of f(x) = sum of prime factors of x.at n=8A047828Number of 3 X n 0..1 arrays with rows and antidiagonals unimodal.at n=9A223681Semiprime numbers that are sandwiched between products of exactly 4 distinct primes (or tetraprimes).at n=8A375964