a(n) is the position of cube of the n-th prime among the powers of primes (A000961).

Terms

a(0) =7a(1) =16a(2) =43a(3) =87a(4) =245a(5) =361a(6) =699a(7) =930a(8) =1514a(9) =2777a(10) =3303a(11) =5280a(12) =6946a(13) =7892a(14) =10027a(15) =13871a(16) =18550a(17) =20323a(18) =26219a(19) =30762a(20) =33157a(21) =41178a(22) =47156a(23) =57135a(24) =72447a(25) =80965a(26) =85429a(27) =94953a(28) =99932a(29) =110400