a(n) is the cototient of n^3.

Terms

a(0) =0a(1) =4a(2) =9a(3) =32a(4) =25a(5) =144a(6) =49a(7) =256a(8) =243a(9) =600a(10) =121a(11) =1152a(12) =169a(13) =1568a(14) =1575a(15) =2048a(16) =289a(17) =3888a(18) =361a(19) =4800a(20) =3969a(21) =5808a(22) =529a(23) =9216a(24) =3125a(25) =9464a(26) =6561a(27) =12544a(28) =841a(29) =19800