a(n) = 2*p(n)*p(n+2) - p(n+1)^2 where p(k) = k-th prime.

Terms

a(0) =11a(1) =17a(2) =61a(3) =61a(4) =205a(5) =205a(6) =421a(7) =573a(8) =585a(9) =1185a(10) =1173a(11) =1501a(12) =2005a(13) =2349a(14) =2737a(15) =2985a(16) =4185a(17) =4173a(18) =4741a(19) =5889a(20) =5877a(21) =7173a(22) =8181a(23) =8569a(24) =9781a(25) =11005a(26) =11005a(27) =12301a(28) =14917a(29) =13477