a(0) = 1, a(n) = 18*n^2 + 2 for n>0.

Terms

a(0) =1a(1) =20a(2) =74a(3) =164a(4) =290a(5) =452a(6) =650a(7) =884a(8) =1154a(9) =1460a(10) =1802a(11) =2180a(12) =2594a(13) =3044a(14) =3530a(15) =4052a(16) =4610a(17) =5204a(18) =5834a(19) =6500a(20) =7202a(21) =7940a(22) =8714a(23) =9524a(24) =10370a(25) =11252a(26) =12170a(27) =13124a(28) =14114a(29) =15140