a(n) = 36*n^2 - 2*n.

Terms

a(0) =34a(1) =140a(2) =318a(3) =568a(4) =890a(5) =1284a(6) =1750a(7) =2288a(8) =2898a(9) =3580a(10) =4334a(11) =5160a(12) =6058a(13) =7028a(14) =8070a(15) =9184a(16) =10370a(17) =11628a(18) =12958a(19) =14360a(20) =15834a(21) =17380a(22) =18998a(23) =20688a(24) =22450a(25) =24284a(26) =26190a(27) =28168a(28) =30218a(29) =32340