a(n) = 289*n^2 - 17.

Terms

a(0) =272a(1) =1139a(2) =2584a(3) =4607a(4) =7208a(5) =10387a(6) =14144a(7) =18479a(8) =23392a(9) =28883a(10) =34952a(11) =41599a(12) =48824a(13) =56627a(14) =65008a(15) =73967a(16) =83504a(17) =93619a(18) =104312a(19) =115583a(20) =127432a(21) =139859a(22) =152864a(23) =166447a(24) =180608a(25) =195347a(26) =210664a(27) =226559a(28) =243032a(29) =260083