a(n) = ((n-th prime)^6-(n-th prime^2))/4.

Terms

a(0) =15a(1) =180a(2) =3900a(3) =29400a(4) =442860a(5) =1206660a(6) =6034320a(7) =11761380a(8) =37008840a(9) =148705620a(10) =221875680a(11) =641431260a(12) =1187525640a(13) =1580340300a(14) =2694803280a(15) =5541089580a(16) =10545132540a(17) =12880092660a(18) =22614594420a(19) =32025069720a(20) =37833555240