a(n) = (prime(n) - 1)*(prime(n) - 3)*(prime(n) - 5)/48.

Terms

a(0) =0a(1) =0a(2) =1a(3) =10a(4) =20a(5) =56a(6) =84a(7) =165a(8) =364a(9) =455a(10) =816a(11) =1140a(12) =1330a(13) =1771a(14) =2600a(15) =3654a(16) =4060a(17) =5456a(18) =6545a(19) =7140a(20) =9139a(21) =10660a(22) =13244a(23) =17296a(24) =19600a(25) =20825a(26) =23426a(27) =24804a(28) =27720a(29) =39711