a(n) = Sum_{k=1..(p-1)*(p-2)} floor((k*p)^(1/3)) where p is the n-th prime.

Terms

a(0) =0a(1) =2a(2) =30a(3) =120a(4) =630a(5) =1122a(6) =2760a(7) =3978a(8) =7392a(9) =15498a(10) =19140a(11) =33390a(12) =46020a(13) =53382a(14) =70380a(15) =102102a(16) =142158a(17) =157530a(18) =210210a(19) =251160a(20) =273492a(21) =348348a(22) =405162a(23) =501468a(24) =652080a(25) =737550a(26) =782952a(27) =879270a(28) =930258a(29) =1038072