Cycle of the inventory sequence (as in A063850) starting with n consists of prime numbers.

Terms

a(0) =39a(1) =93a(2) =349a(3) =394a(4) =439a(5) =493a(6) =934a(7) =943a(8) =999a(9) =1139a(10) =1193a(11) =1319a(12) =1391a(13) =1913a(14) =1931a(15) =1999a(16) =3139a(17) =3193a(18) =3319a(19) =3339a(20) =3391a(21) =3393a(22) =3913a(23) =3931a(24) =3933a(25) =9111a(26) =9139a(27) =9193a(28) =9319a(29) =9391