Incorrect version of A045949.

Terms

a(0) =0a(1) =6a(2) =38a(3) =116a(4) =256a(5) =478a(6) =798a(7) =1236a(8) =1808a(9) =2534a(10) =3430a(11) =4516a(12) =5808a(13) =7326a(14) =9086a(15) =11108a(16) =13408a(17) =16006a(18) =18918a(19) =22164a(20) =25760a(21) =29726a(22) =34078a(23) =38836a(24) =44016a(25) =49638a(26) =55718a(27) =62276a(28) =69328a(29) =76894