a(n) = (6*n)^2.

Terms

a(0) =0a(1) =36a(2) =144a(3) =324a(4) =576a(5) =900a(6) =1296a(7) =1764a(8) =2304a(9) =2916a(10) =3600a(11) =4356a(12) =5184a(13) =6084a(14) =7056a(15) =8100a(16) =9216a(17) =10404a(18) =11664a(19) =12996a(20) =14400a(21) =15876a(22) =17424a(23) =19044a(24) =20736a(25) =22500a(26) =24336a(27) =26244a(28) =28224a(29) =30276