The indices of cubes (of primes) in the 3-almost primes.

Terms

a(0) =1a(1) =5a(2) =30a(3) =82a(4) =328a(5) =551a(6) =1243a(7) =1763a(8) =3112a(9) =6276a(10) =7619a(11) =12972a(12) =17615a(13) =20322a(14) =26514a(15) =37977a(16) =52220a(17) =57703a(18) =76200a(19) =90701a(20) =98470a(21) =124541a(22) =144229a(23) =177395a(24) =229275a(25) =258410a(26) =273908a(27) =306750a(28) =324149a(29) =360724