a(n) = 108*n^2 - 228*n + 114 (n>=2).

Terms

a(0) =90a(1) =402a(2) =930a(3) =1674a(4) =2634a(5) =3810a(6) =5202a(7) =6810a(8) =8634a(9) =10674a(10) =12930a(11) =15402a(12) =18090a(13) =20994a(14) =24114a(15) =27450a(16) =31002a(17) =34770a(18) =38754a(19) =42954a(20) =47370a(21) =52002a(22) =56850a(23) =61914a(24) =67194a(25) =72690a(26) =78402a(27) =84330a(28) =90474a(29) =96834