Numbers n dividing every cyclic permutation of n^4.

Terms

a(0) =1a(1) =3a(2) =9a(3) =21a(4) =27a(5) =73a(6) =99a(7) =111a(8) =271a(9) =693a(10) =707a(11) =777a(12) =819a(13) =909a(14) =999a(15) =2151a(16) =2629a(17) =3441a(18) =3813a(19) =4551a(20) =6987a(21) =7227a(22) =7373a(23) =9999a(24) =18981a(25) =19019a(26) =20007a(27) =20979a(28) =23199a(29) =24453