a(n) = 2809*n^2 - 4618*n + 1898.

Terms

a(0) =89a(1) =3898a(2) =13325a(3) =28370a(4) =49033a(5) =75314a(6) =107213a(7) =144730a(8) =187865a(9) =236618a(10) =290989a(11) =350978a(12) =416585a(13) =487810a(14) =564653a(15) =647114a(16) =735193a(17) =828890a(18) =928205a(19) =1033138a(20) =1143689a(21) =1259858a(22) =1381645a(23) =1509050a(24) =1642073a(25) =1780714a(26) =1924973a(27) =2074850