a(n) = 6*n^2*(2*n + 1).

Terms

a(0) =0a(1) =18a(2) =120a(3) =378a(4) =864a(5) =1650a(6) =2808a(7) =4410a(8) =6528a(9) =9234a(10) =12600a(11) =16698a(12) =21600a(13) =27378a(14) =34104a(15) =41850a(16) =50688a(17) =60690a(18) =71928a(19) =84474a(20) =98400a(21) =113778a(22) =130680a(23) =149178a(24) =169344a(25) =191250a(26) =214968a(27) =240570a(28) =268128a(29) =297714