a(n) = ((n-th prime)^6-(n-th prime)^4)/8.

Terms

a(0) =6a(1) =81a(2) =1875a(3) =14406a(4) =219615a(5) =599781a(6) =3006756a(7) =5864445a(8) =18469506a(9) =74264505a(10) =110822520a(11) =320481531a(12) =593409810a(13) =789743031a(14) =1346791956a(15) =2769558831a(16) =5271052035a(17) =6438316065a(18) =11304778881a(19) =16009359030a(20) =18913228506a(21) =30381063180