Even dodecagonal numbers: a(n) = 4*n*(5*n - 2).

Terms

a(0) =0a(1) =12a(2) =64a(3) =156a(4) =288a(5) =460a(6) =672a(7) =924a(8) =1216a(9) =1548a(10) =1920a(11) =2332a(12) =2784a(13) =3276a(14) =3808a(15) =4380a(16) =4992a(17) =5644a(18) =6336a(19) =7068a(20) =7840a(21) =8652a(22) =9504a(23) =10396a(24) =11328a(25) =12300a(26) =13312a(27) =14364a(28) =15456a(29) =16588